BMW Z4: common faults & what to check
Thinking about buying a used BMW Z4 (2003–2020) in New Zealand? We've documented 10 known faults for this model spanning electrical, suspension, engine, and cooling. 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 BMW Z4
- Odometer history
- Money owing
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10
Critical
$600–$2,500
42
Which BMW Z4 are you looking at?
Petrol
Engine not documented
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Start your free check on this BMW Z4
Pick the engine above first: the Z4 came with 4, and without it the report has to show all of their faults. Pick the engine
Can't confirm for this car
BMW Z4
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.
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What to look out for
Serious issue
Run the VIN through a BMW dealer or the manufacturer's recall checker to confirm the tie rod recall has been completed.
Steering tie rod safety recall (early G29, MY2018-2019 build)
BMW Australia recalled early-build G29 Z4s (along with G20 3 Series and X3M/X4M) because the steering track rods could be damaged by high temperatures and vibration and ultimately break, impairing steering control. The same defect drove recalls of the Z4 and its Toyota GR Supra twin in other markets. The fix is free replacement of both tie rods at a BMW dealer - the buyer's job is simply to confirm the work was done.
What you would notice
Costly issue
Cold-start the car and listen for wastegate rattle and rough running.
N54 high-pressure fuel pump, injector and wastegate problems (sDrive35i/35is)
The twin-turbo N54 in the sDrive35i inherits that engine's full catalogue: high-pressure fuel pump failures (long cranking, misfires, limp mode), leaking or stuttering piezo injectors, and turbo wastegate wear announced by a metallic rattle at cold idle. Early pumps should have been replaced under BMW's extended programmes in some markets, but NZ/AU-delivered and imported cars need the history checked. Individually manageable, collectively these make a neglected 35i the expensive Z4 to own.
What you would notice
Costly issue
Cycle the roof fully at least twice, listening for hesitation, and check the boot floor and roof storage area for hydraulic oil stains or damp.
Retractable hardtop hydraulic and sensor failures (E89)
The E89's two-piece folding metal roof depends on a hydraulic pump, multiple rams, solenoid valves and position sensors; with age the system develops leaks, worn microswitches and relay/solenoid faults that leave the roof stuck half-open. Diagnosis is specialist work and hydraulic component replacement gets expensive quickly. Water ingress into the boot from perished roof seals is a related complaint.
What you would notice
Costly issue
From a cold start, turn lock-to-lock at parking speed and feel for heaviness, stickiness or uneven assist.
Electric power steering column failure (E85/E86)
The E85 Z4's column-mounted electric power steering motor is a notorious failure: the steering suddenly goes very heavy, the EPS warning lights, and often the column stops communicating with diagnostics entirely. Failures can be intermittent at first, which makes them easy for a seller to shrug off. Repair options are a refurbished column/motor or an expensive new unit, so verify it on the test drive.
What you would notice
Costly issue
Ask when the electric water pump and thermostat were last replaced - on a 100,000 km+ car with the original pump, budget for it.
Electric water pump failure (N52 3.0si/sDrive23i/30i, also N54)
The N52 and N54 use a Pierburg electric water pump that commonly fails electronically from around 80,000-130,000 km, often with little warning, causing overheating and limp mode. On the E89 the pump is awkward to reach - workshops often remove the steering rack for access - so labour is a big share of the bill. Many owners replace it preventatively with the thermostat.
What you would notice
Costly issue
Operate the roof at least three times in a row.
Soft-top roof motor failure from water ingress (E85)
The E85's electro-hydraulic roof motor sits low behind the cabin where blocked drainage holes let rainwater pool and flood it, killing the motor. Roof microswitches and the roof module also fail, leaving the top stuck. Many owners relocate the replacement motor higher or into the boot as a permanent fix; keeping the drains clear prevents the problem entirely.
What you would notice
BMW Z4 service schedule
G29 Third Generation · 2018–2026 · sDrive20i (B48) - 2.0L Turbocharged base model
Due by distance
- 60,000 km
Transmission fluid flush to maintain crisp shifts.
- 80,000 km
Keep an eye on the spark plugs and ignition coils for smooth idling.
- 100,000 km
Inspect the cooling system hoses and auxiliary water pump for signs of perishing.
G29 Third Generation · 2018–2026 · M40i (B58) - 3.0L Inline-six performance powerhouse
Due by distance
- 60,000 km
Inspect the cooling system components and water pump housing for any signs of early weeping.
- 80,000 km
Check the transmission fluid condition; the ZF 8-speed is robust but benefits from fresh fluid in the long term.
- 100,000 km
Comprehensive inspection of the engine mount bushings, as they can soften over time with the B58's high torque output.
G29 Third Generation · 2018–2026 · sDrive30i (B48) - 2.0L High-output turbocharged
Due by distance
- 40,000 km
Inspect the run-flat tyres and ensure the brake pads have sufficient life.
- 60,000 km
A sensible time for a proactive transmission fluid flush, even though BMW calls it 'lifetime' oil.
- 80,000 km
Replace the spark plugs and check the water pump, common maintenance points at this stage.
E89 Second Generation · 2011–2016 · sDrive20i (N20) - 2.0L Turbocharged entry model
Due by distance
- 80,000 km
Full inspection of the cooling system components and potential transmission fluid flush.
- 100,000 km
Suspension components like control arm bushings may benefit from a refresh for that 'factory-fresh' handling.
- 120,000 km
Check the health of the fuel injectors and carbon buildup on the intake valves.
E89 Second Generation · 2011–2016 · sDrive28i (N20) - 2.0L High-output turbocharged
Due by distance
- 80,000 km
Inspect the cooling system components and water pump integrity.
- 100,000 km
Check suspension bushings and control arms for signs of wear from NZ road conditions.
- 120,000 km
Have a specialist verify the timing chain assembly condition, key to long-term ownership care.
E89 Second Generation · 2010–2016 · sDrive35is (N54) - Top-spec turbocharged performance
Due by distance
- 60,000 km
Inspect the water pump and thermostat, common items to refresh as the vehicle reaches this mid-life mark.
- 80,000 km
Check the walnut blasting service for the intake valves to maintain the N54's legendary throttle response.
- 100,000 km
Suspension components like dampers may benefit from a check to maintain that sharp BMW handling.
E89 Second Generation · 2009–2016 · sDrive35i (N54) - 3.0L Twin-turbocharged performance
Due by distance
- 80,000 km
Evaluate the cooling system and the condition of the turbo wastegate actuators.
- 100,000 km
Full fluid flush, including transmission fluid and differential oil, to keep the drivetrain feeling sharp.
- 120,000 km
Review the suspension components, specifically the front control arm bushings which may start to soften.
E89 Second Generation · 2009–2011 · sDrive23i (N52) - 2.5L Naturally aspirated inline-six
Due by distance
- 80,000 km
Cooling system components like the water pump and thermostat often reach the end of their service life around this stage.
- 100,000 km
Have the suspension bushings and shock absorbers assessed for fatigue if the car hasn't had a refresh recently.
- 120,000 km
The secondary air injection system and associated vacuum lines may begin to show signs of perishing due to heat cycles.
E89 Second Generation · 2009–2011 · sDrive30i (N52) - 3.0L Naturally aspirated inline-six
Due by distance
- 80,000 km
Proactive check of the water pump and thermostat, as the electronic water pump typically sees increased service necessity around this period.
- 100,000 km
Review the suspension bushings and rear shock mounts to keep the chassis taut and responsive.
- 120,000 km
Comprehensive inspection of the engine oil filter housing gaskets and valve cover gaskets, as the N52 engine often begins to show minor seepage at these seal points by this stage.
E85/E86 First Generation · 2006–2008 · 3.2L (S54) - M Roadster / M Coupe performance flagship
Due by distance
- 60,000 km
Major inspection including differential oil change and valve clearance adjustment check.
- 100,000 km
Focus on the cooling system components like the radiator and water pump, reaching their common service life.
- 120,000 km
Suspension overhaul, focusing on control arm bushings which significantly sharpen the handling when replaced.
E85/E86 First Generation · 2003–2008 · 2.0i (N46) - Entry level roadster
Due by distance
- 100,000 km
Inspect cooling system components, specifically the plastic thermostat housing and radiator hoses.
- 150,000 km
The original suspension struts and rear shock mounts may show their age through a slightly less precise steering feel.
- 200,000 km
Full check of the engine timing chain tensioner so the N46 engine keeps its rhythmic, smooth operation.
E85/E86 First Generation · 2003–2008 · 2.5i (M54/N52) - Mid-range six cylinder
Due by distance
- 100,000 km
Cooling system overhaul, to maintain engine health.
- 150,000 km
Suspension refresh, including shocks and bushings, restores handling.
- 200,000 km
Deep engine maintenance including Vanos seal replacement and oil filter housing gaskets.
E85/E86 First Generation · 2003–2005 · 2.2i (M54) - Smooth inline-six roadster
Due by distance
- 100,000 km
Major cooling system refresh, including the water pump and thermostat.
- 150,000 km
Review the health of the suspension dampers and rear shock mounts for ongoing ride comfort.
- 200,000 km
A significant milestone: the ignition coils and fuel pump may be considered for proactive replacement if not already addressed.
E85/E86 First Generation · 2003–2008 · 3.0i (M54/N52) - High performance inline-six
Due by distance
- 100,000 km
Full refresh of the cooling system components including the water pump and thermostat, as plastic housing components typically reach their service limit around this mark.
- 150,000 km
Inspect the suspension dampers and springs; the original units may have lost their composure and could benefit from an upgrade to restore the factory handling.
- 200,000 km
Have the VANOS solenoid units cleaned or rebuilt, helping maintain the responsive throttle and smooth power delivery these inline-six engines are known for.
See all 10 documented issues
Depends on which engine this BMW Z4 has — 10
Engine, transmission & cooling
01N54 high-pressure fuel pump, injector and wastegate problems (sDrive35i/35is)
Can't confirm for this car
Can't confirm for this car
The twin-turbo N54 in the sDrive35i inherits that engine's full catalogue: high-pressure fuel pump failures (long cranking, misfires, limp mode), leaking or stuttering piezo injectors, and turbo wastegate wear announced by a metallic rattle at cold idle. Early pumps should have been replaced under BMW's extended programmes in some markets, but NZ/AU-delivered and imported cars need the history checked. Individually manageable, collectively these make a neglected 35i the expensive Z4 to own.
A common-rail diesel injector. Contamination damages the nozzle at the tip.
Symptoms to notice
What to check
Ask the seller
02Electric water pump failure (N52 3.0si/sDrive23i/30i, also N54)
Can't confirm for this car
Can't confirm for this car
The N52 and N54 use a Pierburg electric water pump that commonly fails electronically from around 80,000-130,000 km, often with little warning, causing overheating and limp mode. On the E89 the pump is awkward to reach - workshops often remove the steering rack for access - so labour is a big share of the bill. Many owners replace it preventatively with the thermostat.
Symptoms to notice
What to check
Ask the seller
03Plastic cooling system failures - expansion tank, water pump, radiator (E85 M54/N52)
Can't confirm for this carElectrical
01Electric water pump connector short circuit, fire-risk recall REC-006063 (Z4 N20 turbo petrol)
Can't confirm for this car
Can't confirm for this car
On the N20 2.0 litre turbo four-cylinder (Z4 sDrive20i/sDrive28i), oily blow-by liquid from the crankcase ventilation system can collect on the intake air hose and drip onto the electric water pump's plug connector. If liquid gets into the connector it can short circuit, overheat and in rare cases start an engine bay fire. BMW Australia recalled these cars in August 2024 (REC-006063, campaign 0011800700; US campaign 24V608) to inspect and if needed replace the pump and connector and fit a protective shield, free of charge. Ask for proof the recall work has been done.
Symptoms to notice
What to check
Ask the seller
02Retractable hardtop hydraulic and sensor failures (E89)
Can't confirm for this car03Electric power steering column failure (E85/E86)
Can't confirm for this car04Soft-top roof motor failure from water ingress (E85)
Can't confirm for this car
Can't confirm for this car
The E85's electro-hydraulic roof motor sits low behind the cabin where blocked drainage holes let rainwater pool and flood it, killing the motor. Roof microswitches and the roof module also fail, leaving the top stuck. Many owners relocate the replacement motor higher or into the boot as a permanent fix; keeping the drains clear prevents the problem entirely.
Symptoms to notice
What to check
Ask the seller
05Infotainment and electrical gremlins - iDrive freezes, Harman Kardon amp cut-out, headlight condensation (G29)
Can't confirm for this car
Can't confirm for this car
Early G29s show a cluster of electrical niggles: the iDrive display can freeze or reboot, a supplier fault in 2021-era Harman Kardon amplifiers caused audio to cut out entirely, and some cars develop headlight condensation. Most were fixed under warranty via software updates or replacement modules, but on out-of-warranty cars an amplifier or headlight is a real bill. These do not affect drivability but are annoying and worth using in negotiation.
Symptoms to notice
What to check
Ask the seller
Body, brakes, suspension & interior
01Steering tie rod safety recall (early G29, MY2018-2019 build)
Can't confirm for this car
Can't confirm for this car
BMW Australia recalled early-build G29 Z4s (along with G20 3 Series and X3M/X4M) because the steering track rods could be damaged by high temperatures and vibration and ultimately break, impairing steering control. The same defect drove recalls of the Z4 and its Toyota GR Supra twin in other markets. The fix is free replacement of both tie rods at a BMW dealer - the buyer's job is simply to confirm the work was done.
Symptoms to notice
What to check
Ask the seller
Fluid leaks
01Engine oil leaks - valve cover and oil filter housing gaskets (G29 B48/B58)
Can't confirm for this car
Can't confirm for this car
The most commonly reported mechanical complaint on the G29 is engine oil seepage, typically from the valve cover gasket or oil filter housing area as the B48/B58 engines age. Leaks start as a hot-oil smell and light misting before dripping onto the exhaust or belt path. Gasket replacement is routine work but B58 access adds labour.
Symptoms to notice
What to check
Ask the seller
BMW Z4 faults in detail
Other BMW models
BMW Z4 buyer questions
Is the BMW Z4 reliable?
Like any used car, it depends on the specific example and its service history. Across the 10 documented faults for the BMW Z4, the recurring problem areas are electrical, suspension, and engine. A BMW Z4 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 BMW Z4?
We've catalogued 10 known faults for the BMW Z4, covering electrical, suspension, and engine. All 10 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 BMW Z4?
Most single repairs on the BMW Z4 fall between $600–$2,500 at NZ independent-workshop rates. Some of the 10 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 BMW Z4?
Yes. A BMW Z4 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.