I was driving today and when i pressed the clutch down getting ready for a turn i wastched my RPMs drop down to idle speed like normal...BUT...it didnt stop there. It went past the normal 900-1000 mark and died. From then on it has been idling really low like around 300-400 RPMs. I just changed my oil 500 miles ago so that shouldnt be the problem unles i put too heavy of a grade oil in my car for the winter. Tries calling ht dealership but the good old Metro Mitsubishi didnt answer after about 4 tries so i just left a message. there was a similar thread but this problem was a little different so i decided to post a new thread. Sorry if this isnt in the right place and thanks in advance for any help.

 

what weight oil did you use? you'd have to put something REALLY heavy in there to screw with the engine THAT bad. i doubt that it's the oil.

check around for loose/cracked vacuum hoses, make sure the MAF sensor is plugged in... is your MIL on?

 

thanks. i will check around for loose or cracked hoses but what is the MAF sensor and what is the MIL?

 

malfunction indicator lamp - a.k.a. check engine light.

 

when did you last unplug your battery?

 

ACTUALLY...my battery ran down overnight(we had temps of about -6 degrees farrenheit) 2 nights ago and i unplugged it that morning before school and had it on the charger all day and i didnt plug it back in until this morning...

 

the car would shake like holy hell if your MAF wasn't plugged in and you'd more likely throw a CEL.

if a vacuum line is cracked, leaking, missing, fell off, etc. the car would idle like crap all the time, not just when you put your foot on the clutch.

try reseting the ECU. disconnect your battery, pump your brakes a few times, let the car sit for 5 minutes, reconnect the battery, start it up(idle should spike to 4k after a reset), let it idle for 10 minutes, drive it for 15 minutes without beating on it and go through the whole learning cycle (accelerate, decelerate, downshift, ect., turn the car off, restart it......if it's still doing it after the reset and are NO signs of mechanical malfunctions; it's likely the colder more dense air is just effecting your car. in that case you just raise the idle.

 

Thanks. I'll try restting the ecu first thing after school. So all i do is pump the brakes after i unplug the battery? and i dont have any service lights on or anything. and how do i raise the idle? is there a thread on this?

 

anytime. if resetting the ECU works; post it up. if you are still experiencing problems after you reset it; PM me and i'll work you through it. then we'll post up the final solution

mark

 

Any time ECU goes without juice the car must learn to idle again. Do this by bringing it up to operating temp and just let it idle for 10 minutes with out touching anything.

 

Problem solved i think. *knock on wood* I went into the dealership and found out that there was a recall about reflashing the ecu or pcm(?) or something like that. Well they did that and now it seems to idle fine. Thanks for everyones help.

 

If that happens again as it has to me you might want to buy some throttle body cleaner and just spray a little in the there while running and that helped me out. ( Found that in the factory service manual)

 

The Idle Air Control Valve or IAC is also something to check. It is an electrically-operated valve which allows air to bypass the throttle plate in a fuel injected engine to regulate engine idle speed.
It is made from cheap plastic and when it strips, what you described is the result. It happend to me. The part costs about $350 from Mitsu.

 

I would be willing to bet the car car just forgot how to idle from the bat going dead and resetting the ECU.

If it happens again with out resetting the ECU or the battery going dead then start looking for problems. Otherwise I think you are fine.

 

did you have to pay for the reflash? and do you know where to find info on the recall?