Hi guys,

I have bugger all mechanical knowledge and could really use some advice.

My 2001 Pajero IO (the smaller version of what is also known as Montero, I believe) has been using crazy amounts of fuel lately. When I first bought the car it was averaging a little under 10L/100km around the city which was great, but lately it's been using close to 14L/100km (city driving, again) which seems a lot for a small fuel injected 1.8L. It also seems to be getting slightly worse with each fill-up.

Not sure if this could be related or not, but I've also got the dreaded flashing green lights on the super select indicator on the dash. When changing from 4WD back to 2WD they used to flash for a few ks and then stop flashing and all would be good. Now, they simply don't stop flashing at all, even though the transfer lever is back in the 2WD position.

Mitsubishi diagnosed it as needing a new 4WD solenoid switch. I understand this is likely to stop the flashing lights on the dash but if it's only a cosmetic fix and nothing is actually wrong with the transfer between 4WD and 2WD I'd rather put up with the flashing and save the money. I suspected that it might be getting stuck in 4WD when the lights are flashing (hence the drain on fuel), but Mitsubishi reckons that's not the case.

I've checked the air filter (clean) and tyres (38psi), and the car has been regularly serviced, with the last one only a couple months ago. Just wondering if there's anything obvious I'm missing that could be contributing to the poor economy? And does anybody know whether replacing that solenoid would help?

This is really doing my head in. Thanks in advance for the help.

 

I fixed the problem it was the battery arcing off the hood causing all the problems

 

I think maybe this was meant for a different thread? I wish that would fix my problem described above...!

 

paj,

Let's see what the trusty Haynes manual says about troubleshooting excessive fuel consumption:

• Dirty or clogged air element
• Incorrect ignition timing
• Incorrect idle speed
• Low tire pressure
• Fuel leakage
• Choke not operating properly
• Dirty or clogged carburettor jets or fuel injectors
• Air in fuel system

Between you and me, these all sound pretty bogus as far as solving your particular problem. I'm not familiar with your IO model. You said that it's not in 4WD even though the indicator says it is? That could certainly account for your lousy gas mileage if it was. Is there a way to tell? Could you drive for a bit and see if the foreword transfer case is hot? Or drive up on a tall curb so that one of the front wheels is off the ground and have a friend tell if that wheel spins as you slowly drive off? It would be nice if that was your problem because it fits so well with what you're experiencing with the gas.

Is there a way to read the ECM for any fault codes? That might reveal something, although I'm supposing that the dealer would have done that.

Is your idle speed normal?

How's your oxygen sensor? I know this can cause your engine to lose MPG, but it's usually over time as its efficiency degrades, not all at once.

BTW, Your 14L/100km factoid blew my limited American brain

 

Thanks very much for your helpful reply. I've since had the car in sand and found in no uncertain terms that it's not in 4WD, even though the lights on the dash are flashing. So I can at least rule out the car being stuck in 4WD now.

The only fault the dealer could find was with the solenoid valve, which he thought would account for the flashing lights on the dash problem.

The idle speed seems pretty normal, but I'll be sure to get the oxygen sensors checked at the next service.

Thanks again.