aight... i have a 2002 lancer oz automatic. only mods are SRI and axleback exhaust. well, when i was started my car to leave from work today, it idled very rough. it would hold at about 700 rpm steady, then suddenly drop to 400 and nearly die about every 5 seconds, then immediately jump back up to 700. ive had my SRI for almost 10,000 miles and it hasnt ever done this before. well, then after watching the rpms for about 30 seconds, my CEL came on. well, i started to drive home thinking it wasnt much important. when i got home and put the car in park, the car just died. what the hell? then i started it back up, and it started doing that uneven idling again. then i put it in drive and put it right back into park, and it died again. and by this time the car was warmed up and everything... the CEL is still on and it still idles rough. and it just started doing it all of a sudden, nothing gradual, just all of a sudden... any help would be greatly appreciated...

 

Take it in.

 

At the very least, for a piece of mind go to Auto Zone and have them check the codes for the CEL. Then decide if you should take off all your mods before you take it in. Remember, dealers can be dicks, and yes they have to prove your mods did the damage, but if you can avoid the whole ordeal with a bit of elbow grease, you might as well....

 

does anyone know what this problem might be?

 

MAS damage, a sensor might be messed up, something internally, your guess at this point is as good as anyones....

 

well, as a rule of thumb, a good idea is to disconnect your battery for 10 minutes to reset the ECU and the CEL, then reconnect it and start up your car, and let it run idle for 15 minutes. see if the problem persists. if it does, put your stock intake back on and take it into the dealer. if it doesn't, breathe a sigh of relief and get back out on the road.

 

funny i installed my header today, and i get a fluctuation from 700 to 500 rpms.??? car does not stall though, it just seems messed up when idleing???Help

 

dont steal my post....

 

it's the MAS. I'm sure of it. Occasionally with auto, the adaptive shift control messes up the auto fuel map. Try resetting the ecu and see if that fixes it. Also check to make sure the MAS is pluged in tightly. If those two problems don't fix it, I'd take it in.

 

Both of you reset ECU by disconnecting battery for about 5 minutes. then connect and start car. Let it idel for about 10 minutes. Should go away.

 

aight, ill try that. ever since i put my SRI, its been really quite cold, but recently weve had really hot days... could that have something to do with it? i will try reseting the ecu again. also, what about the CEL? will that turn off on its own or do i have to reset the ecu to turn it off?

 

reset ecu.

 

You might want to check you spark plugs.

 

I had a bad vaccuum solenoid that caused all sorts of problems... you could have the same issue. They did try blaming the stalling and bucking and stuff that I got on my air intake... but the CEL didn't lie and once they replaced the solenoid I was all good...

It's a possibility at the least!

Later.

Steve

 

Crank the idle up a little