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Mazda2002–2021 Critical issues documented

Mazda Mazda6: common faults & what to check

Thinking about buying a used Mazda Mazda6 (2002–2021) in New Zealand? We've documented 48 known faults for this model spanning engine, body & rust, transmission, and suspension. Each researched and verified before it's published. The most serious issues here are rated critical. Every one is listed below with its symptoms and repair cost, and each has its own page with where to look and what to ask the seller. Free, no account needed.

Check this exact Mazda Mazda6

  • Odometer history
  • Money owing
  • Reported stolen
  • Ownership history
  • Official NZ vehicle register data
  • NZ owned and operated

Type the plate for the free basics. The full record is a paid check from $13.49, one car at a time, no subscription.

No NZ plate yet, or buying in Australia? Pick the generation and engine and start a free check below. New to KickTyres? How the check works →

48

Documented faults

Critical

Most serious

$400–$2,200

Typical repair

7

Systems covered

Which Mazda Mazda6 are you looking at?

8 generation variants documented. Pick the shape you recognise: the faults, the servicing and the timeline below all narrow to it. Free, no account needed.

Diesel

1 variant documented

Fuel not stated

1 variant documented

Now narrow it to the engine

A 1.8 and a 2.4 of the same car do not fail the same way, so the faults below narrow to the engine as well as the year. Free, no account needed.

Start your free check on this Mazda Mazda6

No plate needed. You get the risk score, the buyer's checklist and the guided inspection for the exact car you picked above — not the whole nameplate.

Mazda Mazda6Engine not picked yet

Pick the engine above first: the Mazda6 came with 5, and without it the report has to show all of their faults. Pick the engine

Free. The paid plate check is separate, and stays optional.

Can't confirm for this car

Mazda Mazda6

Nothing has been narrowed yet, so nothing below is a claim about a particular car. Pick a year and an engine to see which faults apply.

Tell us the engine, or check the engine code on the car, before relying on this.

matched on no vehicle context

What to look out for

The checks worth doing on a Mazda Mazda6 before you hand over any money. Every documented fault is listed below, each with its own page.

  • Serious issue

    Check the dipstick — the level must be between min and max and the oil should not smell of diesel.

    See why

    SkyActiv-D 2.2 oil dilution and DPF problems on short-trip cars

    The GJ/GL's SkyActiv-D 2.2 is refined and economical on the open road, but city-driven cars interrupt DPF regenerations, diesel washes into the sump and the oil level climbs past maximum — Mazda's dipstick even has an 'X' overfill mark for exactly this. Chronic dilution thins the oil and can take out the engine's bottom end or turbo. Mazda Australia handled numerous complaints and extended goodwill on some engines; buying one without open-road history and immaculate servicing is a gamble.

    What you would notice

    • Oil level rising between services / oil above the dipstick X mark
    • Frequent DPF regenerations — raised idle, hot smell, fans running after shutdown
    • DPF or check-engine warning lights
    • White/blue smoke and diesel smell in the oil

    Typically $400–$8,000 to put right.

  • Serious issue

    Pull the engine cover off (it just lifts) and look for black tar around the injector bases.

    See why

    2.2 MZR-CD diesel injector seal failure, DPF clogging and oil dilution

    The GH's 2.2 MZR-CD diesel suffers leaking injector combustion washers (a chuffing noise and black tar around the injectors), a DPF that clogs on short-trip cars, and engine oil level rising above maximum as unburnt diesel from failed DPF regenerations dilutes the oil. Rising oil level is the dangerous one: ignored, it can damage the engine or in extreme cases cause runaway. These engines want open-road use and religious oil changes; a city-driven GH diesel is a money pit.

    What you would notice

    • Chuffing or ticking from the top of the engine
    • Black sticky deposits around the injectors under the engine cover
    • DPF warning light or frequent regenerations (hot smell, raised idle)
    • Oil level above the max mark or oil smelling of diesel
    • Excess smoke after short-trip use

    Typically $800–$4,500 to put right.

  • Serious issue

    Request full service history with fuel filter replacement intervals confirmed — the SkyActiv-D filter should be replaced every 40,000 km.

    See why

    SkyActiv-D High-Pressure Fuel Pump Wear and Failure

    The 2.2L SkyActiv-D common-rail diesel relies on a cam-driven high-pressure fuel pump to generate the 180 MPa injection pressures required by the piezoelectric injectors. The pump internals are susceptible to wear from low-lubricity fuel and metal contamination, particularly on examples with irregular fuel filter servicing, and can produce metallic debris that circulates through the fuel rail and causes injector damage. Failure typically manifests as hard starting, injector rattling, and fault codes for low rail pressure, potentially requiring replacement of both the pump and all four injectors in a worst-case scenario.

    What you would notice

    • Hard starting, especially when cold or after the car has sat overnight
    • Rough or uneven idle with a rattling noise from the injectors
    • P0087 (fuel system pressure low) or P0191 fault codes on OBD scan
    • Severe power loss or engine stall under load
    • Metal particles visible in drained fuel filter housing on inspection

    Typically $1,800–$9,500 to put right.

  • Serious issue

    Cold-start the engine and immediately listen for a chain rattle from behind the timing cover before oil pressure rises.

    See why

    LF-VE 2.0 petrol timing chain stretch and plastic guide wear

    The LF-VE 2.0-litre naturally aspirated petrol fitted to GH-generation Mazda 6 uses a simplex timing chain that stretches over time, particularly when oil changes are delayed or low-grade oil is used. The plastic chain guides wear and can fracture, dropping fragments into the sump. Forum reports and independent mechanic writeups document cold-start rattling progressing to jumped timing and consequential valve damage if ignored.

    What you would notice

    • Cold-start metallic rattle from the front of the engine lasting 2 to 5 seconds
    • Rattle at idle that fades once oil pressure builds
    • Check engine light with camshaft position sensor or VVT correlation codes
    • Rough idle or misfires if timing has jumped
    • Oil consumption above 0.5 litres per 5000 km

    Typically $1,500–$3,200 to put right.

  • Serious issue

    Check oil level and condition on the dipstick.

    See why

    PY-VPTS 2.5T turbo oil feed banjo bolt coking causing oil starvation

    The PY-VPTS 2.5-litre turbocharged petrol fitted to GJ/GL Mazda 6 Atenza shares its architecture with the MX-5 ND/RF and CX-5 2.5T. The turbocharger oil feed banjo bolt contains a small restrictor orifice that accumulates carbon from oil coking, progressively restricting oil flow to the turbocharger bearings. The failure mode is documented in detail on MX-5 forums with teardown photographs and applies equally to the Mazda 6 variant. Without adequate oil flow the turbo bearings fail.

    What you would notice

    • Turbocharger whine or grinding noise at speed
    • Blue smoke from exhaust on deceleration indicating oil burning
    • Oil consumption without visible external leaks
    • Reduced boost and power above 3000 rpm
    • Check engine light with boost pressure or turbo-related codes
    • Oil in the intercooler outlet pipe

    Typically $500–$3,000 to put right.

  • Serious issue

    With the engine warm, open the bonnet and inspect the injector return rail and all banjo fittings for diesel weeping, staining, or dried fuel residue.

    See why

    SKYACTIV-D Fuel Injector Return Pipe Cracking and Fuel Leak

    The high-pressure fuel injector return circuit on the SH-VPTS SKYACTIV-D engine uses a thin-walled plastic return rail and banjo-style connecting pipes that are routed near heat sources. The plastic becomes brittle over time and develops hairline cracks at the banjo fittings or along the rail body, allowing diesel fuel to weep or spray onto hot engine components. This is a documented fire risk. Mazda issued a product improvement campaign for this component in several markets.

    What you would notice

    • Smell of diesel fuel inside or outside the vehicle when the engine is warm, particularly after parking
    • Visible diesel staining or oily film on top of the engine around the injector area
    • Hard starting or extended cranking time as fuel pressure bleeds back through the crack
    • In severe cases, visible dripping fuel or smoke from the engine bay indicating a fire hazard

    Typically $350–$900 to put right.

See all 48 documented issuesEverything researched for the Mazda Mazda6, including 10 rated critical.
Depends on which engine this Mazda Mazda6 has — 48Each of these is documented for one particular engine. Pick the year and engine above to see which of them apply.
Engine, transmission & cooling29

01SkyActiv-D High-Pressure Fuel Pump Wear and Failure

Request full service history with fuel filter replacement intervals confirmed — the SkyActiv-D filter should be replaced every 40,000 km.diesel2012 onwardEngine
OccasionalEngine $1,800–$9,500 to fix

Can't confirm for this car

The 2.2L SkyActiv-D common-rail diesel relies on a cam-driven high-pressure fuel pump to generate the 180 MPa injection pressures required by the piezoelectric injectors. The pump internals are susceptible to wear from low-lubricity fuel and metal contamination, particularly on examples with irregular fuel filter servicing, and can produce metallic debris that circulates through the fuel rail and causes injector damage. Failure typically manifests as hard starting, injector rattling, and fault codes for low rail pressure, potentially requiring replacement of both the pump and all four injectors in a worst-case scenario.

Symptoms to notice

  • Hard starting, especially when cold or after the car has sat overnight
  • Rough or uneven idle with a rattling noise from the injectors
  • P0087 (fuel system pressure low) or P0191 fault codes on OBD scan
  • Severe power loss or engine stall under load
  • Metal particles visible in drained fuel filter housing on inspection

What to check

Request full service history with fuel filter replacement intervals confirmed — the SkyActiv-D filter should be replaced every 40,000 km. On the test drive, listen at idle for injector rattle or ticking inconsistent with normal diesel clatter. Scan for P0087 (fuel rail pressure low) or P0191 fault codes. If a workshop inspection is possible: Connect a diagnostic tool and read live fuel rail pressure — it should stabilise at or above 180 bar at idle.

Where to look: High-pressure pump mounted on the engine front, fuel rail running along the top of the cylinder head

Parts involved: High-pressure fuel pump.

Ask the seller

  • “Has the fuel filter been replaced at every 40,000 km as specified, and do you have receipts?”
  • “Has the car ever had hard-starting issues or been diagnosed with low fuel rail pressure?”
  • “Have any injectors or the high-pressure fuel pump been replaced during ownership?”

02SkyActiv-D 2.2 oil dilution and DPF problems on short-trip cars

Check the dipstick — the level must be between min and max and the oil should not smell of diesel.diesel2012 onwardEngineRead the full fault: symptoms, where to look, what to ask the seller

03MPS L3-VDT Turbo Bearing Failure from Heat Soak

The L3-VDT turbocharged engine in the Mazda 6 MPS suffers from turbocharger bearing failure caused by heat soak after engine shutdown.petrol2006–2008EngineRead the full fault: symptoms, where to look, what to ask the seller

042.2 MZR-CD diesel injector seal failure, DPF clogging and oil dilution

Pull the engine cover off (it just lifts) and look for black tar around the injector bases.diesel2008–2012EngineRead the full fault: symptoms, where to look, what to ask the seller

05LF-VE 2.0 petrol timing chain stretch and plastic guide wear

Cold-start the engine and immediately listen for a chain rattle from behind the timing cover before oil pressure rises.petrol2007–2012Engine
OccasionalEngine $1,500–$3,200 to fix

Can't confirm for this car

The LF-VE 2.0-litre naturally aspirated petrol fitted to GH-generation Mazda 6 uses a simplex timing chain that stretches over time, particularly when oil changes are delayed or low-grade oil is used. The plastic chain guides wear and can fracture, dropping fragments into the sump. Forum reports and independent mechanic writeups document cold-start rattling progressing to jumped timing and consequential valve damage if ignored.

The front of a dual overhead camshaft engine with the timing cover removed, exposing the timing chain and sprockets.Example of the part — not this vehicle

The front of a twin-cam engine with the timing cover off — chain, sprockets and guides.

Logansenf · CC BY-SA 4.0 · Wikimedia Commons

Symptoms to notice

  • Cold-start metallic rattle from the front of the engine lasting 2 to 5 seconds
  • Rattle at idle that fades once oil pressure builds
  • Check engine light with camshaft position sensor or VVT correlation codes
  • Rough idle or misfires if timing has jumped
  • Oil consumption above 0.5 litres per 5000 km

What to check

  1. Cold-start the engine and immediately listen for a chain rattle from behind the timing cover before oil pressure rises.
  2. Check service records for consistent oil changes — infrequent changes accelerate chain and guide wear.
  3. Scan for P0340, P0345, or variable valve timing correlation codes.

Where to look: Timing chain and guides inside the front timing cover, driver-side front of the engine bay

Parts involved: Timing chain.

Ask the seller

  • “Has the timing chain or guides ever been replaced?”
  • “What oil service interval was followed — are full service records available?”
  • “Any cold-start engine rattles that clear after a few seconds?”

06PY-VPTS 2.5T turbo oil feed banjo bolt coking causing oil starvation

Check oil level and condition on the dipstick.petrol2018 onwardEngine
OccasionalEngine $500–$3,000 to fix

Can't confirm for this car

The PY-VPTS 2.5-litre turbocharged petrol fitted to GJ/GL Mazda 6 Atenza shares its architecture with the MX-5 ND/RF and CX-5 2.5T. The turbocharger oil feed banjo bolt contains a small restrictor orifice that accumulates carbon from oil coking, progressively restricting oil flow to the turbocharger bearings. The failure mode is documented in detail on MX-5 forums with teardown photographs and applies equally to the Mazda 6 variant. Without adequate oil flow the turbo bearings fail.

Symptoms to notice

  • Turbocharger whine or grinding noise at speed
  • Blue smoke from exhaust on deceleration indicating oil burning
  • Oil consumption without visible external leaks
  • Reduced boost and power above 3000 rpm
  • Check engine light with boost pressure or turbo-related codes
  • Oil in the intercooler outlet pipe

What to check

  1. Check oil level and condition on the dipstick.
  2. Listen for turbocharger bearing noise (whine or rattle) at idle and under load.
  3. Inspect the intercooler outlet for oil residue.
  4. If a workshop inspection is possible: Remove and inspect the turbo oil feed banjo bolt for internal carbon restriction of the orifice.

Where to look: Turbocharger oil feed banjo fitting at the top of the PE-VPS 2.5T turbocharger, upper rear of the engine

Parts involved: Turbocharger.

Ask the seller

  • “Has the turbo oil feed banjo bolt been cleaned or replaced?”
  • “Any loss of power, unusual turbo noise, or blue exhaust smoke?”
  • “What oil is used and how often has it been changed?”

07SKYACTIV-D Fuel Injector Return Pipe Cracking and Fuel Leak

With the engine warm, open the bonnet and inspect the injector return rail and all banjo fittings for diesel weeping, staining, or dried fuel residue.diesel2013–2019Engine
OccasionalEngine $350–$900 to fix

Can't confirm for this car

The high-pressure fuel injector return circuit on the SH-VPTS SKYACTIV-D engine uses a thin-walled plastic return rail and banjo-style connecting pipes that are routed near heat sources. The plastic becomes brittle over time and develops hairline cracks at the banjo fittings or along the rail body, allowing diesel fuel to weep or spray onto hot engine components. This is a documented fire risk. Mazda issued a product improvement campaign for this component in several markets.

A single common-rail diesel fuel injector photographed against a plain background.Example of the part — not this vehicle

A common-rail diesel injector. Contamination damages the nozzle at the tip.

Panoha · CC BY-SA 3.0 · Wikimedia Commons

Symptoms to notice

  • Smell of diesel fuel inside or outside the vehicle when the engine is warm, particularly after parking
  • Visible diesel staining or oily film on top of the engine around the injector area
  • Hard starting or extended cranking time as fuel pressure bleeds back through the crack
  • In severe cases, visible dripping fuel or smoke from the engine bay indicating a fire hazard

What to check

  1. With the engine warm, open the bonnet and inspect the injector return rail and all banjo fittings for diesel weeping, staining, or dried fuel residue.
  2. Check the underside of the engine cover and the top of the camshaft housing for oily black diesel film.
  3. Smell for raw diesel under the bonnet when the engine is at operating temperature.
  4. Confirm whether Mazda's product improvement campaign (recall) for the return pipe has been completed.

Where to look: Top of the engine, fuel injector return rail running parallel to the camshaft cover

Parts involved: Fuel injector.

Ask the seller

  • “Has Mazda's injector return pipe recall or product improvement campaign been completed on this car?”
  • “Have you ever noticed a diesel smell under the bonnet after a drive?”
  • “Can I inspect the engine top for any fuel staining before purchase?”

08Denso low-pressure fuel pump recall — engine stall risk (GL petrol)

Run the VIN through the Mazda NZ or ACCC recall checker, or phone a Mazda dealer, and get written confirmation the fuel pump recall is complete.petrol2018–2020Engine
OccasionalEngine $0–$700 to fix

Can't confirm for this car

GL Mazda6 petrols built around 2018-2020 are included in the worldwide Denso low-pressure fuel pump recall: the impeller can swell and stop the pump, causing hard hot-starting, hesitation or the engine cutting out while driving. Mazda Australia and Mazda NZ replaced pumps free under recall campaigns, but not every car has been through. Verify by VIN — an outstanding recall is a free fix but a real safety issue until done.

Symptoms to notice

  • Engine won't restart when hot
  • Hesitation or stumble under load
  • Engine stalls while driving
  • Fuel-pressure related check-engine codes

What to check

Run the VIN through the Mazda NZ or ACCC recall checker, or phone a Mazda dealer, and get written confirmation the fuel pump recall is complete. For a JDM Atenza import, ask the importer for the Japanese recall completion evidence.

Where to look: Fuel pump inside the fuel tank, under the rear seat

Parts involved: Water pump.

Ask the seller

  • “Has the Denso fuel pump recall been completed on this VIN?”
  • “Has it ever stalled or struggled to start when hot?”

09SkyActiv-G 2.5 Excessive Engine Oil Consumption

Check the oil level on the dipstick and compare against the service interval sticker — significant drop between services is the primary indicator.petrol2013–2017Engine
OccasionalEngine $200–$5,500 to fix

Can't confirm for this car

A proportion of 2.5L SkyActiv-G engines produced between 2013 and 2017 exhibit above-normal oil consumption attributed to piston ring design tolerances that allow combustion gases and oil to pass under certain light-load operating conditions. Affected engines can consume 0.5–1.0 litre per 1,000 km without visible external leaks or significant blue smoke, making the issue easy to miss without careful dipstick monitoring between services. Mazda issued an internal technical bulletin addressing inspection criteria, and in some markets authorised piston ring replacement under extended goodwill policies, though this is rarely available on higher-mileage second-hand examples.

Symptoms to notice

  • Oil level dropping noticeably between 5,000 km service intervals without external leaks
  • Blue smoke from exhaust visible on cold start or during engine braking
  • Fouled or oil-coated spark plugs found during routine inspection
  • Occasional misfire codes linked to oil-contaminated spark plugs
  • Catalytic converter damage or failure caused by oil passing through the combustion chamber

What to check

  1. Check the oil level on the dipstick and compare against the service interval sticker — significant drop between services is the primary indicator.
  2. Inspect the spark plugs for oil fouling (dark wet deposits on the electrode).
  3. Look for blue tinge in the exhaust on a cold start and during deceleration from highway speeds.
  4. Ask the seller how often they add oil between changes.

Where to look: Internal engine — piston rings and cylinder bores

Ask the seller

  • “Do you ever need to top up the oil between scheduled services, and if so by how much?”
  • “Has a Mazda dealer or workshop ever investigated or diagnosed an oil consumption issue?”
  • “Have the spark plugs been replaced recently, and was there any sign of oil fouling on the old plugs?”

10SkyActiv-D Variable Geometry Turbo Actuator Failure

Scan for P0045, P0046, P0047, P0299 or turbo underboost/overboost codes.diesel2012 onwardEngine
OccasionalEngine $600–$5,500 to fix

Can't confirm for this car

The 2.2L SkyActiv-D uses a variable geometry turbocharger controlled by an electronic stepper-motor actuator that positions the VGT vanes to regulate boost pressure across the rpm range. The actuator is prone to internal gear wear and motor failure, particularly on higher-mileage examples, causing the vanes to default to a fixed position and triggering limp mode with a turbo-related fault code. A seized actuator can also cause the vanes themselves to stick, requiring turbocharger replacement rather than the actuator alone if left unaddressed.

Symptoms to notice

  • Limp mode triggered under hard acceleration
  • P0045 or P0299 turbo underboost fault codes
  • Flat, unresponsive power delivery especially between 1800–3000 rpm
  • Whistling or variable-pitch turbo noise under load
  • Engine management warning light with loss of performance

What to check

  1. Scan for P0045, P0046, P0047, P0299 or turbo underboost/overboost codes.
  2. On a test drive accelerate firmly from 1500 rpm — a healthy SkyActiv-D builds strong progressive boost; a stuck actuator produces flat, sluggish acceleration with limp-mode activation above 3000 rpm.
  3. Inspect the actuator unit on the rear of the turbo for cracked housing or corrosion.

Where to look: Turbocharger assembly, rear of the engine block on the exhaust manifold side

Parts involved: Turbocharger.

Ask the seller

  • “Has the turbocharger or its actuator ever been replaced or rebuilt?”
  • “Has the car ever entered limp mode or shown a boost-related fault code?”
  • “Can we do a full OBD scan including live boost pressure data before purchase?”

11SkyActiv-Drive 6-Speed Automatic Torque Converter Shudder

2012 onwardTransmission
OccasionalTransmission $250–$4,200 to fix

Can't confirm for this car

The GJ/GL Mazda6 fitted with the SkyActiv-Drive 6-speed automatic transmission can develop a characteristic shudder or vibration felt through the drivetrain at light throttle between 60–100 km/h, caused by slip in the torque converter lock-up clutch. The clutch engagement zone becomes rough when the transmission fluid degrades or when the friction material in the converter wears, producing a resonance that mimics a misfire or rough road surface. A fluid change with the correct Mazda-specification M-V ATF often resolves early-stage shudder; advanced cases require torque converter replacement.

A cutaway automatic transmission torque converter showing the internal turbine and stator.Example of the part — not this vehicle

A torque converter, sectioned. The lock-up clutch inside is what shudders.

No machine-readable author provided. BerndB~commonswiki assumed (based on copyright claims). · CC BY-SA 3.0 · Wikimedia Commons

Symptoms to notice

  • Rhythmic shudder or vibration at steady highway speeds between 60–100 km/h
  • Shudder that disappears when the accelerator is released or pressed harder but returns at light throttle
  • Vibration felt through the seat, floor, and steering wheel simultaneously
  • Transmission fluid with dark colour or burnt smell
  • Occasional harsh or delayed upshift under light acceleration

What to check

During the test drive, cruise at a steady 70–90 km/h on a flat road at light throttle and feel for a rhythmic shudder or vibration through the seat and steering wheel. Manually shift down then up to disengage and re-engage the torque converter lock-up to see if the shudder disappears in a specific gear range. Check the transmission fluid colour and smell — dark burnt fluid accelerates converter wear.

Where to look: Automatic transmission and torque converter, central tunnel beneath the cabin

Parts involved: Torque converter.

Ask the seller

  • “Has the transmission fluid ever been changed, and with which specification fluid?”
  • “Has the car ever shuddered or vibrated at highway cruising speeds?”
  • “Has a transmission technician ever inspected or diagnosed any gearbox concerns?”

12SkyActiv-D EGR Cooler Cracking

Check for white chalky deposits inside the EGR valve bore.diesel2012 onwardEngine
OccasionalEngine $1,200–$3,500 to fix

Can't confirm for this car

The SkyActiv-D 2.2 diesel EGR cooler cracks from thermal cycling allowing coolant into the intake system and producing white chalky deposits.

Symptoms to notice

  • White smoke from exhaust on startup and white deposits in the EGR bore
  • Coolant level dropping without a visible external leak

What to check

Check for white chalky deposits inside the EGR valve bore. Perform a combustion gas test on the coolant. White smoke on startup in a warm climate is characteristic.

Where to look: EGR cooler on diesel intake system

Parts involved: EGR valve.

Ask the seller

  • “Has the skyactiv-d egr cooler cracking been inspected or repaired?”

13SH-VPTS 2.2D diesel injector nozzle coking causing hard cold start

Cold-start the vehicle when ambient temperature is below 10 degrees Celsius and note cranking duration and idle quality.diesel2013 onwardEngine
OccasionalEngine $1,200–$3,500 to fix

Can't confirm for this car

The SH-VPTS 2.2-litre diesel engine used in GJ/GL Mazda 6 diesel develops injector nozzle coking from incomplete combustion on short-trip or urban driving cycles, causing hard starting in cold conditions, uneven idle, and eventually misfires. NZ and AU diesel owners report the problem is exacerbated by low-quality fuel and infrequent highway runs. Injector cleaning or replacement is required once misfires develop.

A single common-rail diesel fuel injector photographed against a plain background.Example of the part — not this vehicle

A common-rail diesel injector. Contamination damages the nozzle at the tip.

Panoha · CC BY-SA 3.0 · Wikimedia Commons

Symptoms to notice

  • Extended cranking before engine fires in cold weather
  • Rough or uneven idle on cold startup
  • Visible smoke on cold start that does not clear quickly
  • Reduced fuel economy and power loss
  • Cylinder-specific misfire fault codes on scan tool

What to check

  1. Cold-start the vehicle when ambient temperature is below 10 degrees Celsius and note cranking duration and idle quality.
  2. Scan for injector balance rate faults or P030X misfire codes.
  3. Ask whether the vehicle has had predominantly city or highway use.

Where to look: Fuel injectors in the cylinder head, top of the SH-VPTS 2.2-litre diesel engine

Parts involved: Fuel injector.

Ask the seller

  • “Has the car had injectors professionally cleaned or replaced?”
  • “Any hard starting in cold weather or rough idle from cold?”
  • “What has the typical driving pattern been — mostly city or regular highway trips?”

14GH Automatic Transmission Torque Converter Shudder

Test-drive at 50-80 km/h under light throttle on a flat road.petrol2006–2012TransmissionRead the full fault: symptoms, where to look, what to ask the seller

15Ageing 4/5-speed auto — flared or harsh shifts when fluid is neglected

Test drive until fully warm — at least 15 minutes — and pay attention to the 2-3 shift under moderate throttle.petrol2002–2008Transmission
OccasionalTransmission $300–$3,500 to fix

Can't confirm for this car

The GG's conventional automatics are fundamentally durable but most have never had a fluid service, and by 150,000-200,000 km neglected units flare between 2nd and 3rd, shift harshly when hot, or shudder lightly at lock-up. A fluid and filter service helps a mildly symptomatic box; one that bangs or slips already needs overhaul money, which is usually uneconomic on a GG.

Symptoms to notice

  • Revs flare between gears, especially 2nd-3rd
  • Harsh clunky shifts once warmed up
  • Light shudder at 60-80 km/h steady throttle (lock-up)
  • Dark or burnt-smelling transmission fluid

What to check

  1. Test drive until fully warm — at least 15 minutes — and pay attention to the 2-3 shift under moderate throttle.
  2. Check the transmission fluid dipstick: fluid should be red-pink and not smell burnt.
  3. Ask for any invoice showing a transmission service; absence of one on a 200,000 km car is a bargaining chip.

Where to look: Automatic transmission; fluid dipstick in the engine bay

Ask the seller

  • “Has the automatic transmission fluid ever been changed?”
  • “Does it ever flare or clunk between gears when hot?”

16Dual-mass flywheel and clutch failure (GH diesel manual)

diesel2008–2012Transmission
CommonTransmission $1,800–$3,000 to fix

Can't confirm for this car

Manual GH diesels use a dual-mass flywheel that wears out, often before the clutch itself: rattling at idle that disappears when the clutch pedal is pressed, vibration, and eventually juddering take-offs. Replacement requires a DMF and clutch kit together, making it one of the more expensive routine failures on this car. Cars used for towing or urban crawling wear DMFs fastest.

Symptoms to notice

  • Rattle or chatter at idle that stops when the clutch pedal is pressed
  • Judder on take-off
  • Vibration through the pedal
  • Clonk when engaging or releasing drive

What to check

With the engine idling in neutral, listen for a rattly chatter from the bellhousing, then press the clutch pedal — if the noise stops, the DMF is worn. Do a couple of uphill take-offs and feel for judder. Ask if the clutch has been done and whether the flywheel was replaced at the same time (a solid-flywheel conversion is a common, acceptable fix — ask which was fitted).

Where to look: Flywheel and clutch between engine and gearbox, low at the front of the car

Parts involved: Clutch.

Ask the seller

  • “Has the clutch or flywheel been replaced, and is there an invoice?”
  • “Does it rattle at idle and go quiet with the clutch pedal down?”

17SkyActiv-D EGR Valve and Cooler Carbon Fouling

Scan for P0400, P0401, P0402, P0403 fault codes even if the MIL is not currently lit.diesel2012 onwardEngineRead the full fault: symptoms, where to look, what to ask the seller

18SkyActiv-D intake manifold and EGR soot clogging

On the test drive, accelerate firmly from 50 to 100 km/h and feel for hesitation or a power hole.diesel2012 onwardEngine
CommonEngine $900–$2,500 to fix

Can't confirm for this car

Because the SkyActiv-D runs a low compression ratio and heavy EGR, its intake manifold and ports coke up with oily soot on short-trip cars, causing flat spots, limp mode and rough running from around 100,000-150,000 km. A manual intake strip-and-clean is hours of labour. Cars that have done sustained highway running fare far better.

Symptoms to notice

  • Flat spots or hesitation under acceleration
  • Intermittent limp mode with reduced power
  • Check-engine light with EGR or airflow codes
  • Rough idle when warm

What to check

On the test drive, accelerate firmly from 50 to 100 km/h and feel for hesitation or a power hole. Ask whether the intake or EGR has ever been cleaned and look for an invoice. A diagnostic scan for stored EGR/boost codes before purchase is cheap insurance on any SkyActiv-D.

Where to look: Intake manifold and EGR valve on the engine, under the bonnet

Parts involved: Intake manifold, EGR valve.

Ask the seller

  • “Has the intake manifold or EGR ever been cleaned out?”
  • “Has it ever gone into limp mode?”

19Automatic Transmission Torque Converter Shudder

Test drive at 80-100 km/h with very light throttle and feel for rhythmic vibration.petrol2002–2007Transmission
CommonTransmission $400–$2,500 to fix

Can't confirm for this car

Atenza automatic transmission develops torque converter lock-up shudder under light throttle at highway cruise.

A cutaway automatic transmission torque converter showing the internal turbine and stator.Example of the part — not this vehicle

A torque converter, sectioned. The lock-up clutch inside is what shudders.

No machine-readable author provided. BerndB~commonswiki assumed (based on copyright claims). · CC BY-SA 3.0 · Wikimedia Commons

Symptoms to notice

  • Rhythmic vibration at highway speed under light throttle
  • Shudder clears under firm acceleration as lock-up clutch releases

What to check

Test drive at 80-100 km/h with very light throttle and feel for rhythmic vibration. ATF that is brown rather than red indicates degraded fluid.

Where to look: Automatic transmission and torque converter assembly

Parts involved: Torque converter.

Ask the seller

  • “Has the automatic transmission torque converter shudder been inspected or repaired?”

202.3 MZR timing chain tensioner rattle

Cold-start the engine and listen at the front timing cover area for chain rattle.petrol2002–2012EngineRead the full fault: symptoms, where to look, what to ask the seller

216-speed Aisin automatic transmission solenoid wear

Test drive through all gear changes at light and firm throttle and note any jerkiness, shudder, or hesitation.2007–2015Transmission
OccasionalTransmission $900–$2,000 to fix

Can't confirm for this car

The Aisin 6-speed automatic fitted to GH Mazda 6 and retained on early GJ models develops solenoid body wear, causing harsh or delayed gear changes, converter shudder, and occasional limp-home mode. Fluid degradation from infrequent servicing accelerates internal wear. The solenoid pack (valve body) is the primary failure component. Documented on owner forums across NZ and Australia.

Symptoms to notice

  • Harsh or jerky gear changes particularly on the 1-2 and 2-3 upshifts
  • Shudder or flare on kickdown
  • Delayed engagement when selecting Drive or Reverse
  • Transmission warning light or limp-home mode
  • Burnt smell from transmission fluid

What to check

  1. Test drive through all gear changes at light and firm throttle and note any jerkiness, shudder, or hesitation.
  2. Check transmission fluid colour — it should be red or pink, not brown or black.
  3. Ask when the fluid was last changed and whether it was done with a flush.

Where to look: Automatic transmission solenoid pack inside the valve body, accessible from underneath the vehicle

Parts involved: Mechatronic / valve body.

Ask the seller

  • “Has the automatic transmission fluid been changed, and when?”
  • “Any harsh shifts, shudder, or transmission warning lights?”
  • “Has the transmission had any workshop attention?”

22SKYACTIV-G Intake Valve Carbon Deposit Buildup

Assess idle quality after the engine reaches operating temperature; persistent roughness suggests significant deposits.petrol2012 onwardEngineRead the full fault: symptoms, where to look, what to ask the seller

23GJ Six-Speed Automatic Torque Converter Shudder at Cruise

2012–2018Transmission
OccasionalTransmission $400–$1,800 to fix

Can't confirm for this car

The GJ Atenza fitted with the six-speed SkyActiv-Drive automatic transmission uses a lock-up torque converter that engages in partial lock-up at light-throttle highway cruise speeds (typically 60-100 km/h) to improve fuel economy. When the transmission fluid degrades or the fluid level is slightly low, the converter's torsional damper springs fail to smooth the lock-up engagement, causing a characteristic shuddering or vibration through the drivetrain at steady cruise. The shudder disappears when the throttle is increased or released, distinguishing it from driveline vibration. Mazda updated the ATF specification and issued a flush-and-refill service bulletin to address the condition.

A cutaway automatic transmission torque converter showing the internal turbine and stator.Example of the part — not this vehicle

A torque converter, sectioned. The lock-up clutch inside is what shudders.

No machine-readable author provided. BerndB~commonswiki assumed (based on copyright claims). · CC BY-SA 3.0 · Wikimedia Commons

Symptoms to notice

  • Rhythmic shuddering or vibration felt through the cabin at 80-100 km/h on light steady throttle, disappearing when throttle is released or increased
  • Shudder absent at the same road speeds in lower gears or when the converter is unlocked
  • Transmission fluid dark brown or with a burnt odour on the dipstick at operating temperature
  • Occasional harsh or delayed upshift when the fluid has significantly degraded

What to check

Road test at a steady 80-100 km/h on light throttle — hold a constant speed and observe for a rhythmic vibration felt through the seat, steering wheel, or floor that is not present at other speeds or throttle positions. Check the transmission fluid condition and level with the vehicle at operating temperature. Dark or burnt-smelling fluid indicates degraded ATF. If a workshop inspection is possible: Confirm with a scan tool that the converter is commanded into lock-up at the time the shudder occurs.

Where to look: Automatic transmission torque converter, accessible from underneath at the bellhousing

Parts involved: Torque converter.

Ask the seller

  • “Does the car vibrate at a steady 80-100 km/h cruise with light throttle?”
  • “When was the automatic transmission fluid last changed, and what fluid specification was used?”
  • “Has the transmission ever been scanned for fault codes or inspected by a specialist?”

24RF 2.0D diesel EGR valve and cooler carbon blockage

Check inlet manifold for soot buildup restricting airflow.diesel2007–2012EngineRead the full fault: symptoms, where to look, what to ask the seller

25GJ 2.2 SKYACTIV-D DPF Differential Pressure Sensor Failure Causing Regeneration Failure

Scan for DPF-related codes: P2002 (DPF efficiency below threshold), P2452/P2453 (DPF pressure sensor range/performance).diesel2012–2018Engine
CommonEngine $350–$900 to fix

Can't confirm for this car

The SH-VPTS 2.2-litre diesel in the GJ Atenza uses a differential pressure sensor to measure the pressure drop across the diesel particulate filter and calculate soot loading. The sensor and its small-bore hose connections are exposed to exhaust heat cycling and condensed soot-laden moisture. When the sensor drifts or fails, the ECU receives an incorrect soot-load reading: it either never triggers a forced regen (allowing the DPF to block) or triggers continuous regen cycles that burn excess fuel and overheat the catalyst. A blocked DPF results in limp-home mode.

Symptoms to notice

  • DPF warning light illuminated, sometimes accompanied by engine management light and limp-home power restriction
  • Noticeably more frequent or continuous DPF regeneration cycles indicated by elevated idle temperature and fuel consumption
  • P2452 or P2453 DPF pressure sensor fault codes stored in the ECU
  • Rough, hesitant power delivery and black smoke if the DPF has reached a blocked state

What to check

  1. Scan for DPF-related codes: P2002 (DPF efficiency below threshold), P2452/P2453 (DPF pressure sensor range/performance).
  2. With a live data scanner, compare sensor reading against expected pressure drop at idle and at 2000 rpm.
  3. Inspect the two small silicone hoses connecting the sensor to the DPF taps for cracks or blockages.
  4. Check for soot paste in the hose bores.

Where to look: DPF differential pressure sensor mounted on the exhaust tunnel under the vehicle, with hose connections to the inlet and outlet of the DPF canister

Parts involved: Differential, Diesel particulate filter.

Ask the seller

  • “Has the DPF warning light ever come on, and was the cause investigated?”
  • “Has the vehicle been driven mainly on short trips or urban cycles?”
  • “Has the DPF ever required forced regeneration or professional cleaning?”

26L5-VE 2.5 EGR valve sticking rough idle

Allow engine to reach full operating temperature and observe idle quality.petrol2007–2013EngineRead the full fault: symptoms, where to look, what to ask the seller

27L3-VDT Ignition Coil-on-Plug Failure Causing Misfire

Scan for P030x misfire codes.petrol2002–2007Engine
CommonEngine $200–$600 to fix

Can't confirm for this car

L3-VDT ignition coils fail causing misfires, rough running, and check engine light with P030x codes.

A four-cylinder ignition coil rail removed from an engine, beside a steel rule for scale.Example of the part — not this vehicle

A coil-on-plug ignition rail, removed. One coil per cylinder.

Cschirp · CC BY-SA 3.0 de · Wikimedia Commons

Symptoms to notice

  • Rough running and misfire under load with check engine light
  • Misfire moving to a different cylinder when coils are swapped confirms the fault

What to check

Scan for P030x misfire codes. Swap coils between cylinders — if the misfire moves, the coil is faulty.

Where to look: Ignition coils on each spark plug — top of engine

Parts involved: Ignition coil.

Ask the seller

  • “Has the l3-vdt ignition coil-on-plug failure causing been inspected or repaired?”

28L3-VDT Turbo Inlet Pipe Cracking and Boost Loss

Firmly accelerate from 2000rpm and listen for hissing from the engine bay.petrol2002–2007Engine
CommonEngine $100–$350 to fix

Can't confirm for this car

The L3-VDT 2.3T turbo inlet pipe rubber section hardens and cracks with age, releasing boost pressure and causing a flat spot on acceleration with an audible hiss from the engine bay.

Symptoms to notice

  • Flat spot under acceleration with audible hiss from the engine bay
  • Power temporarily returning when throttle is released

What to check

Firmly accelerate from 2000rpm and listen for hissing from the engine bay. Inspect the turbo inlet pipe rubber section for cracking especially at bends and clamp ends.

Where to look: Turbo inlet pipe rubber section and clamps in the engine bay

Parts involved: Turbocharger.

Ask the seller

  • “Has the l3-vdt turbo inlet pipe cracking been inspected or repaired?”

29Timing chain and VVT rattle on 2.5 L5 petrol at high mileage

Cold-start the car yourself and listen at the front of the engine for a rattle in the first few seconds.petrol2008–2012Engine
OccasionalEngine $1,200–$2,500 to fix

Can't confirm for this car

The GH's 2.5 petrol is the safe pick, but high-mileage or oil-change-neglected examples develop a rattle on cold start from a worn variable valve timing actuator and stretched timing chain — the same L-series weakness Mazda saw on related 2.3/2.5 engines. It progresses slowly, but a full chain, guides and VVT actuator job is labour-intensive. Cars with documented regular oil changes rarely suffer it.

The front of a dual overhead camshaft engine with the timing cover removed, exposing the timing chain and sprockets.Example of the part — not this vehicle

The front of a twin-cam engine with the timing cover off — chain, sprockets and guides.

Logansenf · CC BY-SA 4.0 · Wikimedia Commons

Symptoms to notice

  • Rattle for a few seconds on cold start
  • Persistent light rattle at idle when worn further
  • Check-engine light with cam/crank correlation codes

What to check

Cold-start the car yourself and listen at the front of the engine for a rattle in the first few seconds. Review the service history for oil-change intervals — anything beyond 10,000 km intervals raises the risk. A quick OBD2 scan for stored P0016/P0011-type codes is worthwhile.

Where to look: Timing chain and VVT actuator at the front of the engine, behind the timing cover

Parts involved: Timing chain.

Ask the seller

  • “Does it rattle on cold start?”
  • “Can you show the oil change history?”
Electrical3

01Electric Power Steering Rack Rattle

Drive over rough surfaces at low speed and listen for rattle from the steering rack area.2012 onwardElectrical
CommonElectrical $600–$2,200 to fix

Can't confirm for this car

EPS rack develops internal rattle at low speeds over rough surfaces.

Symptoms to notice

  • Knocking or rattling from steering rack area at low speeds
  • Vibration through steering wheel during slow manoeuvring

What to check

Drive over rough surfaces at low speed and listen for rattle from the steering rack area.

Where to look: Electric power steering rack assembly

Parts involved: Steering rack.

Ask the seller

  • “Has the electric power steering rack rattle been inspected or repaired?”

02GJ MZD Connect Infotainment Screen Delamination

View the infotainment screen from multiple angles with the display active and also with it off (use a torch).2013–2021Electrical
CommonElectrical $400–$1,400 to fix

Can't confirm for this car

The GJ Mazda6 uses a multi-layer bonded LCD display for the MZD Connect infotainment system. The optical adhesive layer between the glass digitiser and the LCD panel degrades with heat cycling, causing air bubbles, white clouding, or full separation visible as a mobile liquid layer between the screen surfaces. The condition worsens with direct sunlight exposure. Mazda initially covered this under warranty in some markets but out-of-warranty replacements require the full head unit to be swapped as the screen is not separately serviceable at dealer level.

Symptoms to notice

  • White or grey cloudy patches visible on the infotainment screen, typically worse at screen edges and in areas exposed to direct sunlight
  • Air bubbles visible between the screen glass layers, appearing as defined oval shapes that shift position when pressure is applied
  • Touch input becomes inaccurate or non-responsive in areas where delamination has progressed
  • Screen appearance deteriorates noticeably after the vehicle has been parked in direct sun

What to check

  1. View the infotainment screen from multiple angles with the display active and also with it off (use a torch).
  2. Look for: white cloudy patches, air bubble outlines (typically starting at the edges and migrating inward), or a rippled liquid-layer appearance.
  3. Check the outer corners and lower edge of the screen first as delamination typically starts there.
  4. Test touchscreen responsiveness across the full surface — delaminated areas often lose touch accuracy.

Where to look: Centre dashboard, 7-inch or 8-inch MZD Connect display unit

Ask the seller

  • “Has the infotainment screen ever been replaced or repaired under warranty for bubbling or delamination?”
  • “Can I inspect the screen in bright light and from multiple angles before agreeing to purchase?”
  • “Does the touchscreen respond accurately across the entire surface?”

03MAZDA CONNECT CMU Infotainment System Freezing and Unresponsiveness

Check the current CMU firmware version in the system settings menu — versions below 59.00.502 are known to have stability problems.2012–2018Electrical
CommonElectrical $150–$700 to fix

Can't confirm for this car

The GJ Atenza (2012-2018) fitted with Mazda Connect uses a Connectivity Master Unit (CMU) running an embedded Linux-based OS. The CMU is known to lock up completely, leaving the display frozen or blank, the audio system silent, and the backup camera inoperative. The freeze requires a hard reboot (either by holding the volume knob or disconnecting the battery). The root cause is a combination of memory leak issues in early firmware versions and SD card corruption in the map/firmware storage. Mazda issued multiple CMU software updates to address stability, but many imported units have never been updated.

Symptoms to notice

  • Screen freezes on a static display mid-drive and does not respond to touch or physical controls
  • Audio cuts out entirely and cannot be restored without a hard CMU reboot
  • Backup camera fails to display when reverse gear is selected
  • System spontaneously reboots while driving, showing the Mazda startup logo before resuming

What to check

Check the current CMU firmware version in the system settings menu — versions below 59.00.502 are known to have stability problems. Attempt to replicate the freeze by using Apple CarPlay or Android Auto simultaneously with the navigation, then switching between sources rapidly. Eject the map SD card and inspect it for corrosion on the contacts. Ask the owner whether the screen has ever gone black or frozen mid-drive.

Where to look: Centre dashboard infotainment head unit (CMU), SD card slot on the left side of the unit

Ask the seller

  • “Has the infotainment screen ever frozen or gone blank while driving?”
  • “Has the CMU software been updated to the latest version?”
  • “Has the map SD card ever been replaced?”
Body, brakes, suspension & interior14

01GG/GH Front Subframe and Engine Cradle Corrosion

2002–2012Body & RustRead the full fault: symptoms, where to look, what to ask the seller

02GH Rear Subframe Trailing Arm Mount Corrosion

2007–2012Body & RustRead the full fault: symptoms, where to look, what to ask the seller

03GG/GH Front Subframe and Lower Control Arm Mount Corrosion

Probe the subframe rails and mounting flanges with a screwdriver — sound steel will resist, corroded sections will flex or crumble.2002–2012Body & RustRead the full fault: symptoms, where to look, what to ask the seller

04GG/GH Rear Wheel Arch and Sill End Rust Perforation

Look for bubbling paint, rust staining through the arch liner, or perforation holes.2002–2012Body & RustRead the full fault: symptoms, where to look, what to ask the seller

05Severe rear wheel arch and sill rust (GG)

Run a fingernail under both rear arch lips feeling for bubbles and filler; a small magnet will fall off bogged arches.2002–2008Body & RustRead the full fault: symptoms, where to look, what to ask the seller

06GH/GJ Rear Suspension Trailing Arm Bushing Failure and Knuckle Cracking

Then grip at 6 and 12 o'clock and check for vertical play indicating collapsed trailing arm bushings.2006–2015Suspension
OccasionalSuspension $400–$2,200 to fix

Can't confirm for this car

The GH and early GJ Mazda6 rear multi-link suspension uses large-diameter rubber bushings in the trailing arm to rear knuckle interface. These bushings deteriorate and collapse under high-kilometre use, causing significant toe and camber variation under cornering loads. Separately, a stress fracture has been documented at the rear knuckle spindle-to-body junction on higher-mileage GH vehicles subjected to pothole impacts or kerb strikes, particularly on the driver's side. A cracked knuckle is a roadworthy failure and creates unpredictable handling.

Symptoms to notice

  • Rear tyre wear concentrated on the inner or outer edge suggesting toe or camber deviation from collapsed bushings
  • Clunking or banging from the rear suspension over road imperfections, distinct from shock absorber noise
  • Rear wheel alignment that cannot be corrected to within Mazda specification using standard adjustment
  • Visible crack line or stress fracture at the knuckle casting, detectable under close inspection with a torch on a hoist

What to check

Then grip at 6 and 12 o'clock and check for vertical play indicating collapsed trailing arm bushings. Inspect the rear knuckle casting (the upright holding the wheel bearing) visually with a torch for any hairline cracks, particularly around the spindle and where the trailing arm bolts attach. Have an alignment check done — significantly off-spec rear toe that cannot be corrected by adjustment indicates bushing collapse. If a workshop inspection is possible: On a hoist, grip each rear wheel at the 9 and 3 o'clock positions and push/pull to check for lateral play in the knuckle or trailing arm.

Where to look: Rear multi-link suspension, trailing arm-to-knuckle bushings; rear wheel hub/knuckle casting

Ask the seller

  • “Has the car had a four-wheel alignment recently, and were the rear values within specification?”
  • “Is there any knocking or banging from the rear over bumps that hasn't been diagnosed?”
  • “Has the car been kerb-struck or had any notable pothole impacts at the rear?”

07Rear Subframe Mounting Bush Deterioration

Inspect the four subframe mounting points for cracked or extruded rubber visible around the metal crush sleeves.2012 onwardSuspension
CommonSuspension $500–$1,400 to fix

Can't confirm for this car

The GJ/GL Mazda6 rear subframe uses large rubber-bonded mounting bushes that are prone to cracking and delamination from age and road salt exposure, a pattern well-documented in Australian and New Zealand fleet vehicles from approximately 70,000 km onwards. Deteriorated bushes allow the rear subframe to shift under cornering and braking loads, creating vague handling, a tendency to tramline, and a characteristic knocking or clonking noise over uneven surfaces. Left unaddressed, excessive subframe movement accelerates wear in the rear geometry components including toe links and lateral arms.

Symptoms to notice

  • Knocking or clonking noise from the rear over bumps or during braking
  • Vague or wandering steering feel despite correct alignment settings
  • Rear-end instability or tramline tracking on grooved roads
  • Uneven or accelerated rear tyre wear despite recent alignment
  • Vibration through the floor under moderate to hard braking

What to check

Inspect the four subframe mounting points for cracked or extruded rubber visible around the metal crush sleeves. On the test drive, brake moderately from 60 km/h and listen for a dull knock from the rear as the subframe shifts. If a workshop inspection is possible: With the car on a hoist, physically push and pull the rear subframe to check for perceptible movement — any measurable shift indicates failed bushes.

Where to look: Rear undercarriage, four mounting points where the rear subframe bolts to the body

Ask the seller

  • “Have the rear subframe bushes ever been inspected or replaced?”
  • “Has the car had any rear suspension knocking or handling complaints?”
  • “When was the last four-wheel alignment performed and did the technician note any compliance issues?”

08Front Lower Control Arm Rear Bush Wear — Wander

Tap around the bush exterior and listen for a hollow sound indicating internal fluid loss.2012 onwardSuspensionRead the full fault: symptoms, where to look, what to ask the seller

09Rear Disc Brake Caliper Stiction and Seizure from Corrosion

After a short test drive, immediately touch each rear wheel centre (not the disc) — a seized caliper will make the wheel warm or hot from brake drag.2002–2018Brakes
CommonBrakes $400–$1,100 to fix

Can't confirm for this car

The Atenza uses sliding-pin rear disc brake calipers. On low-mileage or urban-use examples the rear discs are rarely heated sufficiently to drive off moisture, allowing corrosion to form on the disc contact surfaces and the caliper slide pins. The slide pins seize in their bores, preventing the caliper from releasing fully after brake application. The result is the rear brake pads dragging constantly against a corroded disc, causing uneven wear, disc warping, binding, and pulling. This is compounded on imported examples that have sat in storage or been used primarily for short runs.

Symptoms to notice

  • Rear wheel(s) noticeably warm to the touch after a short drive with no heavy braking
  • Distinct brake drag or pulling to one side under light deceleration
  • Uneven rear disc wear with glazed or grooved contact patches, and deep rust on uncovered disc sections
  • Pulsation through the brake pedal caused by disc thickness variation from uneven dragging wear

What to check

After a short test drive, immediately touch each rear wheel centre (not the disc) — a seized caliper will make the wheel warm or hot from brake drag. Inspect the rear discs for a heavily rusted annular band at the outer or inner edge (indicating the pad is only contacting part of the disc). If a workshop inspection is possible: With the vehicle on a hoist, attempt to slide each rear caliper by hand along its pins — a free caliper should move easily with light thumb pressure; a seized one will not move or move only with significant force.

Where to look: Rear brake calipers and slide pins, rear brake discs inner and outer faces

Parts involved: Brake disc and pads, Body corrosion.

Ask the seller

  • “Do the rear brakes drag or does the car pull under light braking?”
  • “When were the rear brake pads and discs last replaced?”
  • “Has the vehicle sat unused for extended periods?”

10Front Lower Arm Ball Joint Wear

Inspect the boot for splitting.2002–2007Suspension
CommonSuspension $350–$800 to fix

Can't confirm for this car

Front lower arm ball joints wear causing clunking and handling imprecision.

The front wheel of a car splayed outward with the lower control arm hanging down after a ball joint separation.Example of the part — not this vehicle

A separated lower ball joint: the control arm has dropped and the wheel has splayed out under the guard.

Elfix · CC0 · Wikimedia Commons

Symptoms to notice

  • Clunking from front suspension over bumps
  • Imprecise handling feel when cornering

What to check

Inspect the boot for splitting. If a workshop inspection is possible: With vehicle raised, lever the lower arm and check for ball joint play.

Where to look: Front lower suspension control arms

Parts involved: Ball joint.

Ask the seller

  • “Has the front lower arm ball joint been inspected or repaired?”

11Front lower control arm ball joint wear

With the wheels on the ground, push and pull each front tyre at 3 and 9 o'clock to check for lateral ball joint play.2007 onwardSuspension
CommonSuspension $350–$700 to fix

Can't confirm for this car

Both GH (2007-2012) and GJ/GL (2013-present) Mazda 6 platforms develop front lower control arm ball joint wear at moderate mileage. The ball joint is integral to the pressed-steel lower arm on most variants, so wear typically requires full arm replacement. NZ mechanics and WOF inspectors consistently flag this item on cars over 100,000 km, and it appears in owner reports spanning both generations.

The front wheel of a car splayed outward with the lower control arm hanging down after a ball joint separation.Example of the part — not this vehicle

A separated lower ball joint: the control arm has dropped and the wheel has splayed out under the guard.

Elfix · CC0 · Wikimedia Commons

Symptoms to notice

  • Clunking from front suspension over bumps or when turning
  • Vague or wandering steering feel
  • Uneven tyre wear across the front axle
  • Pulling to one side under braking

What to check

With the wheels on the ground, push and pull each front tyre at 3 and 9 o'clock to check for lateral ball joint play. Inspect the ball joint rubber boot for cracking or grease loss, which indicates accelerated wear. If a workshop inspection is possible: On a hoist, lever the lower arm upward to check for vertical play.

Where to look: Front lower control arm, both driver and passenger sides

Parts involved: Ball joint.

Ask the seller

  • “Have the front lower arms or ball joints been replaced?”
  • “Any WOF advisories or failures for front suspension?”
  • “Any clunking or looseness over bumps or when parking?”

12Brake Caliper Guide Pin Seizure

Check for pulling under braking.2012 onwardBrakes
CommonBrakes $150–$500 to fix

Can't confirm for this car

Front brake caliper guide pins seize from corrosion causing uneven pad wear.

Symptoms to notice

  • Vehicle pulling to one side under braking
  • One front disc hotter than the other after moderate use

What to check

  1. Check for pulling under braking.
  2. Feel for uneven wheel heat.
  3. Inspect guide pins.

Where to look: Front brake calipers

Parts involved: Brake disc and pads.

Ask the seller

  • “Has the brake caliper guide pin seizure been inspected or repaired?”

13Rear Multi-Link Bush Collapse

Inspect rear suspension arm bushes for cracking.2012 onwardSuspension
CommonSuspension $400–$1,200 to fix

Can't confirm for this car

Rear multi-link suspension arm bushes harden and collapse causing rear knocking and imprecision.

Symptoms to notice

  • Knocking from rear suspension over rough surfaces
  • Imprecise rear handling feel

What to check

  1. Inspect rear suspension arm bushes for cracking.
  2. Push arms — any movement indicates collapsed bushes.

Where to look: Rear multi-link suspension arm bushes

Ask the seller

  • “Has the rear multi-link bush collapse been inspected or repaired?”

14Worn front control arm bushes and ball joints causing clunks and vague steering

Drive at open-road speed and note whether the car tracks straight without constant correction.2002–2008Suspension
CommonSuspension $350–$1,000 to fix

Can't confirm for this car

GG Mazda6s are hard on their front lower control arm bushes and ball joints; by now most unrestored cars knock over bumps and feel vague or wandery at motorway speed. The rear multi-link setup also wears its bushes, showing as uneven rear tyre wear. Complete aftermarket arms are the economical fix but it adds up across the front end.

The front wheel of a car splayed outward with the lower control arm hanging down after a ball joint separation.Example of the part — not this vehicle

A separated lower ball joint: the control arm has dropped and the wheel has splayed out under the guard.

Elfix · CC0 · Wikimedia Commons

Symptoms to notice

  • Clunking from the front over bumps
  • Vague or wandering steering at 100 km/h
  • Uneven front tyre wear
  • Shudder through the wheel under braking

What to check

  1. Drive at open-road speed and note whether the car tracks straight without constant correction.
  2. Listen for front-end knocks on rough seal.
  3. Check front tyre shoulders for uneven wear and ask when the control arms or bushes were last replaced — on a 20-year-old car, 'never' means budget for them.

Where to look: Front lower control arms and ball joints behind the front wheels

Parts involved: Ball joint.

Ask the seller

  • “Have the front control arms or bushes been replaced?”
  • “Did the last WoF or service note any suspension play?”
Fluid leaks2

01GJ SKYACTIV-D High-Pressure Injector Return Pipe Cracking

With the engine warm and running, a fine diesel mist or drip at any pipe union indicates a crack.diesel2012–2018Fluid Leaks
OccasionalFluid Leaks $450–$1,300 to fix

Can't confirm for this car

On the GJ Atenza fitted with the SKYACTIV-D 2.2 diesel, the plastic injector leak-off (return) pipes that run between the four injectors and return excess fuel to the tank are subject to heat embrittlement and vibration fatigue. The pipe material hardens and develops hairline cracks at the injector union fittings. This allows high-pressure diesel to weep into the engine bay, creating a fire risk and causing fuel trim faults as the ECU compensates for incorrect rail pressure.

A single common-rail diesel fuel injector photographed against a plain background.Example of the part — not this vehicle

A common-rail diesel injector. Contamination damages the nozzle at the tip.

Panoha · CC BY-SA 3.0 · Wikimedia Commons

Symptoms to notice

  • Persistent diesel fuel odour from the engine bay, strongest immediately after a warm shutdown
  • Visible fuel staining or weeping at the top of one or more injectors where the return pipe connects
  • Rough running or hard starting accompanied by rail pressure low codes as cracked pipes introduce air into the return circuit
  • Elevated fuel consumption with no other identified cause

What to check

With the engine warm and running, a fine diesel mist or drip at any pipe union indicates a crack. Check for fuel smell in the engine bay especially after a warm start. If a workshop inspection is possible: Remove the engine cover and inspect the injector return pipes and unions closely with a torch — look for fuel staining (diesel leaves a dark oily residue or dry white salt residue) around the injector tops.

Where to look: Top of the engine on the injector rail, where individual plastic return pipes connect to each injector body

Parts involved: Fuel injector.

Ask the seller

  • “Has a diesel smell ever been noticed from the engine bay?”
  • “Have the injector return pipes or any fuel system components been replaced?”
  • “Has the vehicle ever had a fuel rail pressure fault code?”

022.3T MPS turbo oil feed hose seepage

Inspect the turbocharger oil feed hose along its full length and both banjo fitting ends for seepage, oil staining, or soft spots.petrol2005–2008Fluid Leaks
OccasionalFluid Leaks $230–$950 to fix

Can't confirm for this car

The L3-VDT 2.3L turbocharged engine in the GG-generation Mazda6 MPS supplies pressurised engine oil to the turbocharger bearings via a braided oil feed hose and banjo fittings. With age and repeated heat cycling the rubber lining of the hose hardens and cracks, and the seals at the banjo fitting connection points deteriorate, leading to seepage or weeping of oil. Any reduction in oil feed pressure to the turbocharger risks bearing starvation under boost, which causes accelerated turbocharger wear and ultimately catastrophic bearing failure. Oil contacting hot exhaust components creates a smoke or burning smell in the engine bay. Hose replacement is essential at the first sign of seepage.

Symptoms to notice

  • Burning oil smell from engine bay, especially under boost
  • Oil residue or wetness visible around the turbo oil feed hose or fittings
  • Unexplained oil consumption without obvious external pooling
  • Smoke from engine bay if oil contacts exhaust or turbo housing

What to check

  1. Inspect the turbocharger oil feed hose along its full length and both banjo fitting ends for seepage, oil staining, or soft spots.
  2. Check the turbo oil inlet port and surrounding area for contamination.
  3. Check oil level against known consumption and look for any evidence of oil on the undertray.

Where to look: Turbocharger oil feed hose from engine block oil gallery to turbocharger inlet, driver's side of engine bay

Parts involved: Turbocharger.

Ask the seller

  • “Has the turbo oil feed hose been inspected or replaced?”
  • “Any history of oil consumption, burning smell, or smoke from the engine bay?”
  • “Has the turbocharger ever been rebuilt or replaced?”

Mazda Mazda6 faults in detail

Each of these has its own page: the symptoms, where to look, what to ask the seller and what the repair costs. Free, no account needed.

2.2 MZR-CD diesel injector seal failure, DPF clogging and oil dilutionCritical · Engine2.3 MZR timing chain tensioner rattleMajor · EngineFront Lower Control Arm Rear Bush Wear — WanderMajor · SuspensionGG/GH Front Subframe and Engine Cradle CorrosionCritical · Body & RustGG/GH Front Subframe and Lower Control Arm Mount CorrosionMajor · Body & RustGG/GH Rear Wheel Arch and Sill End Rust PerforationMajor · Body & RustGH Automatic Transmission Torque Converter ShudderMajor · TransmissionGH Rear Subframe Trailing Arm Mount CorrosionCritical · Body & RustL5-VE 2.5 EGR valve sticking rough idleMajor · EngineMPS L3-VDT Turbo Bearing Failure from Heat SoakCritical · EngineRF 2.0D diesel EGR valve and cooler carbon blockageMajor · EngineSevere rear wheel arch and sill rust (GG)Major · Body & RustSkyActiv-D 2.2 oil dilution and DPF problems on short-trip carsCritical · EngineSkyActiv-D EGR Valve and Cooler Carbon FoulingMajor · EngineSKYACTIV-G Intake Valve Carbon Deposit BuildupMajor · Engine

What these repairs cost on other cars

Some of the Mazda Mazda6’s documented faults are repairs other models share. Each page lists the documented NZ cost for every model it affects.

Other Mazda models

Mazda Mazda337 documented faultsMazda CX-536 documented faultsMazda Mazda233 documented faultsMazda BT-5026 documented faultsMazda CX-926 documented faultsMazda MX-526 documented faults

Mazda Mazda6 buyer questions

Is the Mazda Mazda6 reliable?

Like any used car, it depends on the specific example and its service history. Across the 48 documented faults for the Mazda Mazda6, the recurring problem areas are engine, body & rust, and transmission. A Mazda Mazda6 with a full service history and no signs of the issues listed on this page can be a sound buy but each one needs to be checked individually before you commit.

What are the most common problems with a used Mazda Mazda6?

We've catalogued 48 known faults for the Mazda Mazda6, covering engine, body & rust, and transmission. All 48 are written out in full on this page, with the symptoms to notice, what to inspect, and typical repair costs for each. Free to read, no account needed.

How much do repairs cost on a Mazda Mazda6?

Most single repairs on the Mazda Mazda6 fall between $400–$2,200 at NZ independent-workshop rates. Some of the 48 documented faults cost less and a few cost considerably more, and no one car needs them all. Knowing which ones to look for before you view is what lets you negotiate the price down or walk away.

Should I get a pre-purchase inspection on a Mazda Mazda6?

Yes. A Mazda Mazda6 inspection focused on its known weak points is the single best way to avoid an expensive mistake. KickTyres gives you a guided, model-specific inspection plus a market valuation and negotiation figure for $24.90 far less than the cost of missing one of the faults on this page.