Mitsubishi Pajero Engine Problems

The Mitsubishi engine is generally sound and doesn’t normally use excessive oil. If and when they do it’s usually found to be worn valve stem seals, and it that’s the case you won’t find and leaks or see any sign on the tailpipe.

The trade tells us that there is no issue with your model, but make sure you fit a quality sequential injection system, such as the Impco one that Mitsubishi released as a factory option for the 380.

I too have read the claims made by makers of these chips as well, but I don’t have the evidence that confirms the benefits, so I would leave well enough alone. By your admission the Pajero is doing the job, so I wouldn’t change it.

They are prone to using oil because of worn valve stem seals, so I would have a mechanic check that.

Backfiring is usually caused by a problem with the ignition system, and usually fixed by replacing the spark plug leads. It happens when the LPG/air mix in the intake manifold is ignited by a random spark, and it often results in the air intake and filter being blown away. It is unusual to damage the catalytic converter and have the computer meltdown, and damage to the auto trans is unheard of. Check the ignition system and certainly replace the spark plug leads, and have the auto checked by a specialist.

What you’ve been told, that it’s a sticking lifter, is the most likely explanation and it’s generally not a serious issue. Change the oil and filter and that should cure it, but it could be that one or more lifters are faulty and in need of replacement.

It’s either getting too much fuel or not enough during the cold phase. If it’s getting too much fuel it’s likely to be due to worn fuel injectors that are leaking down while the car sits overnight and essentially flooding the engine. Although you say you have replaced the injectors, you don’t say you used new parts, so I would still look there. It could be though that the temperature sensor that tells the computer that it needs to boost the fuel for a cold start is faulty and the message is not getting through.

It sounds like it’s not getting fuel. Get some aerosol starter fluid, like “Start Ya Bastard”, and spray that into the carburetor and then crank the engine. If it starts you can be assured it’s a fuel supply problem. In that case it could be a faulty needle and seat in the carby that’s letting the fuel drain back into the tank while it’s sitting not running.

The cost of the plugs and leads is about right, and the labour charge is about right for three hours work. If all he did was fit the plugs and leads it's expensive, but if he investigated the cause of the misfire beyond simply fitting those parts the labour charge is probably about right as well.

The LPG consumption is very good, almost too good to believe, and the petrol consumption is woeful. I would expect that you should be able to get 17.5L/100 km or so on LPG, but you're getting much better than that, and about 14 L/100 km on petrol and you're doing much worse than that. I would take it to another LPG installer, one that is familiar with the system fitted to your car and have them thoroughly check it on both fuels.