CriticalCommonEngine

Mitsubishi Pajero Sport: Coolant loss, overheating and head gasket blow-by, service campaign 020116 (2.5 4D56 diesel, built before March 2014)

Coolant loss, overheating and head gasket blow-by, service campaign 020116 (2.5 4D56 diesel, built before March 2014) is a common engine fault on the Mitsubishi Pajero Sport on the 2009–2014 cars, and we rate it critical. Putting it right costs $2,200 to $8,000 at New Zealand independent workshop rates. Below is what goes wrong, the symptoms to notice on a test drive, where to look, and what to ask the seller before you hand over any money. It is one of 15 documented faults on the Mitsubishi Pajero Sport.

Vehicle: Mitsubishi Pajero Sport
Engine: 4D56
Years: 2009–2014
Fuel: diesel
System: Engine

This page covers the Mitsubishi Pajero Sport as a model. Some faults only affect particular engines or build years — enter a plate below to narrow the list to one car.

All Mitsubishi Pajero Sport faults15 documented faults on this model

What you are looking at

What goes wrong

Mitsubishi machined the top face of the 4D56 cylinder block too roughly on engines built before 18 March 2014, so the head gasket never sealed properly against it and combustion pressure could push past into the coolant. In November 2014 Mitsubishi opened preventative service campaign 020116 for PB/PC Challengers with the 2.5-litre 4D56HP diesel, citing engines overheating from 'repetitive coolant evaporation' after high-load driving such as towing, and inadequate head gasket sealing at the upper block surface. Australian owner forums carry accounts of head gaskets failing on low-kilometre cars, including a 2014 build at 60,000 km with tracking marks visible between cylinders. The pattern is coolant that vanishes with nothing on the ground, then an overheat, then a bill that can run into a head skim or a new engine. Mitsubishi changed the machining process around 2014, so later cars are the safer buy.

What you would notice

Coolant level falling with nothing ever visible on the driveway
Temperature gauge climbing when towing, on hills or on a hot day
Bubbling or gurgling in the coolant header tank with the engine running
White steam from the exhaust that does not clear once warm
Creamy or mayonnaise-like residue under the oil filler cap

How to check it

Where to look. Cylinder head gasket between the head and the top face of the block; coolant header tank at the front of the engine bay

Check the coolant level in the header tank with the engine cold and ask the seller straight out how often they top it up — 'now and then' is the answer that matters here.
Once the engine is properly cold, look at the underside of the oil filler cap for a creamy mayonnaise-like film, which points at coolant getting into the oil.
With the engine idling and warm, look into the coolant header tank for a steady stream of bubbles rising through it, and sniff the tank for an exhaust smell.
Take the car up a decent hill on the test drive, or ask to tow nothing but drive it hard for ten minutes, and watch the temperature gauge the whole way.
Ask whether service campaign 020116 was carried out and whether the head gasket has ever been replaced, and ask for the invoice if it has.

Parts involved: Head gasket.

What it costs to put right

$2,200 to $8,000 at New Zealand independent workshop rates. That is for this job on its own, not for the car.

An estimate, in NZD, for the repair as normally carried out. What a specific car costs depends on which part has failed and what it damaged on the way — treat this as the floor for a negotiation, not a quote.

Ask the seller

“How often do you top up the coolant?”
“Was Mitsubishi service campaign 020116 carried out on this vehicle?”
“Has the head gasket ever been replaced, or the head skimmed? Can I see the invoice?”
“Has this vehicle been used for towing?”

Now check the Mitsubishi Pajero Sport you are actually looking at

Everything above is true of the model, and it is free. What it does not tell you is whether THIS car has been looked after: its odometer history and whether the reading has ever gone backwards, whether there is still money owing on it, whether it has been reported stolen, how many owners it has had and what it is really worth today. That comes from the official records for that plate. Enter the plate for the free details, or get the full history and a market valuation from $13.49.

Not sure what you would be paying for? See what a full KickTyres check includes.

Where this comes from

The failure described above is documented in the sources below. The inspection instructions and the cost estimate are KickTyres’ own interpretation of them.

Australian Car.Reviews — 'Recalls & faults: Mitsubishi Mk.2 Challenger (2009-15)', preventative service campaign 020116 (November 2014), 4D56HP engines built before 18 March 2014
Pajero 4WD Club of Victoria forum, PB/PC Challenger section — 'Looks like a blown head gasket' thread
ReDriven — 'Used Mitsubishi Challenger (PB/PC) review': head gasket problems stemming from improper block machining at the factory
Whirlpool Forums — 'Triton/Challenger overheating issue' thread

Mitsubishi Pajero Sport buyer questions

Is coolant loss, overheating and head gasket blow-by, service campaign 020116 (2.5 4d56 diesel, built before march 2014) serious on a Mitsubishi Pajero Sport?

We rate it critical and common on the Mitsubishi Pajero Sport. Mitsubishi machined the top face of the 4D56 cylinder block too roughly on engines built before 18 March 2014, so the head gasket never sealed properly against it and combustion pressure could push past into the coolant. In November 2014 Mitsubishi opened preventative service campaign 020116 for PB/PC Challengers with the 2.5-litre 4D56HP diesel, citing engines overheating from 'repetitive coolant evaporation' after high-load driving such as towing, and inadequate head gasket sealing at the upper block surface. Australian owner forums carry accounts of head gaskets failing on low-kilometre cars, including a 2014 build at 60,000 km with tracking marks visible between cylinders. The pattern is coolant that vanishes with nothing on the ground, then an overheat, then a bill that can run into a head skim or a new engine. Mitsubishi changed the machining process around 2014, so later cars are the safer buy.

How much does it cost to fix on a Mitsubishi Pajero Sport?

$2,200 to $8,000 at New Zealand independent workshop rates. That figure is for this job on its own. A car showing the symptoms on this page is usually worth either walking away from or negotiating down by at least the repair figure.

Which Mitsubishi Pajero Sport years are affected?

Our research records this fault on the 2009–2014 Mitsubishi Pajero Sport. Build dates move around, especially on imported cars, so treat the range as the years to look hardest at rather than a guarantee either way. The official records tell you the exact build and first registration date for the car in front of you.

How do I check for it before I buy?

Check the coolant level in the header tank with the engine cold and ask the seller straight out how often they top it up — 'now and then' is the answer that matters here. Once the engine is properly cold, look at the underside of the oil filler cap for a creamy mayonnaise-like film, which points at coolant getting into the oil. With the engine idling and warm, look into the coolant header tank for a steady stream of bubbles rising through it, and sniff the tank for an exhaust smell. Take the car up a decent hill on the test drive, or ask to tow nothing but drive it hard for ten minutes, and watch the temperature gauge the whole way. Ask whether service campaign 020116 was carried out and whether the head gasket has ever been replaced, and ask for the invoice if it has. Look here: Cylinder head gasket between the head and the top face of the block; coolant header tank at the front of the engine bay