It seems my car has developed some bad habits. Usually after it's been running a bit and gets good and warm, especially after having been driven stop and go, the car will develop a lumpy idle (sounds like it's not running on all 4 cylinders) and then eventually die. At this point it becomes damn near impossible to start up without stomping on the accelerator and basically revving it and gradually letting it down. After a bit it will go back into a semi-steady idle, but generally it will not run well again at low RPMs until it's cooled off.

Very odd. It has left me in a few awkward positions recently.

Here's the possibilities I'm entertaining:

1. (This is the one I think is most likely) Bad grounds. I think my ignition system and/or possibly fuel injectors are having trouble due to poor grounding.

2. In combination with #1 the higher than avg underhood temps created due to my car being turbocharged could be causing further electrical distress.

3. Fouled sparks (which doesn't compute because it runs fine when warm)

4. Bad coil pack (same as above)

5. Timing is off. (Possible but also unlikely because she idles fine at the same coolant and presumably oil temp. I tuned the idle and timing when the car was warm so this seems the least likely of the bunch to me)

Also looking for outside ideas or anyone who's had similar experiences.

Tonight I'm changing my oil, checking the timing, and checking the spark plugs. The car is driveable for the most part, but I'd really like to resolve this as soon as possible to avoid getting myself killed. Any and all suggestions are welcome.

 

your really deep into this, and i wish you lots of luck because i know how it is to deal with troubles of the engine (currently on my 5th week without my car), but if you think it is the gorund the only thing to do is check them all obviously, maybe a project when its light out or if you have some lights or w/e, but from the way you describe it sounds like something is cutting out (fuel maybe?) because you say its start fine and all, but when it cuts off, you have to jam the pedal and rev it up to keep it on, i doubt it would be timing because if it was it wouldn't be working properly the second you start it, so like YOU said, lol just check your ground lines

btw, have you resolved your fuel problem at all? or is this now your only problem? one thing leads to another unfortunately

 

I have no free time. It just so happens my class was cancelled tonight because my prof is an elected official and tonight is election night. I'm doing this at night because after I swing by Pep Boys, then go to vote, I'll actually have some free time tonight.

The two problems may be related.

 

I had a problem like this on another car....

It was the first O2 sensors that was wrong. It sent a bad signal to the ECM.

The ECM think it run lean, but in reality, It run too rich. I don't know how many miles you have with your car, try another o2 sensors if you have one.

 

Brand new WBO2 in there. Standalone engine management. My idle AFR is around 13.9:1 AFR. I have other electrical problems as well which keep me thinking it's electrical either related to grounding, heat or both.

 

at first i was goign to say maybe it was a sensor, but i doubted it because your using the full stand alone, heat is HUGE with those turbos under our hood as both you and i know, but that could melt wires possibly which ive seen happen to lancers, but again it should be something you could see if that, its got to be a combo of elctrical and heat, hopefully you put all new wires in yourself so you know what to look for, dude your problems scale so far beyond anyone elses big problems here, i hate not knowing an answer :\

 

andrew, check for some sort of vacuum leak as well. i've had some weird **** happen because of vacuum loss.

i agree it may be a grounding issue, but it sounds that the car doesn't want to properly bring in air when you warm up. check your MAF and make sure the wires are all right there.

that's about all i can think of off the top of my head for now

 

wouldnt heat increase the e- flow rate of a grounding cable?

 

I haven't been able to find any vaccuum leaks. I constantly check (see my last thread where I discovered I had an exhaust leak while looking for a vac/boost leak). I plan on replacing all my silicone hosing in the near future though in an attempt to rule out another variable.

I stand by this being heat and/or electrical though due to the circumstances. A vac leak should cause problems when cold as well as when warm. For the record, my coolant doesn't get TOO hot, it just gets hot.

Gaijin, I can't say I know enough about electricity to even answer.

 

Had a problem once with a car running hot, the fuel would vapor before the car would overheat. It would die and then restart after a few minutes. Just an idea, you said that you have high temps under the hood. Good Luck!!

 

what other electrical probs. are you having?

 

EGT is not high though. It's just dissipating a lot from the manifold and turbo causing the whole underhood area to heat up.

Other electrical problems, lights dim when opening/closing windows, dome light does not activate when doors are opened but lights when switched "on", battery holds charge, but voltage drops significantly after only a couple hours after driving.

 

bad or going bad alternator might be cause of electrical probs as well, since your coolant isnt gettin super hot it probably isnt your thermostat, possibly bad spark plug/plug wires.. I had something similar happen to me with my 92 bronco, one of the plug wires got out of the holders and touched the engine and it killed hte wire.. and like you even brought up, possibly a ground somewhere is loose or worse, missing... but still shouldnt totally kill the car since we there are 4-5 ground points..

 

I read that you are using a stand alone engine mgt. Does it utilize some sort of throttle position sensor? When they go bad or lose their calibration, the symptons you describe can occur. Too rich or lean is common, but it sounds rich. Just a guess without testing it, if you have one. Hope this helps.

Jason

 

AFR is right where I want it. TPS reads fine.