Top of the mourning to ya.
I've got a 1993 plymouth acclaim 3.0L V6.
When I start the car(it starts every time) It seems to idle ok at around 1000rpms. And it will drive fine for a little while, untill when I believe it hits regular running temperature, at this point the idle speed drops down to about 600 and the it idles very rough, when you decellerate quickly or come to a stop the rpms start jumping around varying form 800 to about 0 where the car obveously stalls. It will start right up again but the problem is still present. It gets worse the longuer you're on the road, but as long as you're moving at at least 40 clics it's faily smooth. And the only way to keep her going in traffic is to put her in neutral and keep your foot on the gas( But the revs are still jumping around when I'm doing this). My mechanic can't figure it out, I brought it to another mechanic and he replaced the MAP sensor, that did nothing. I replaced the oil, gas, and air filters recently. I'm thinking of the EGR valve or air sensor but I'd rather hear some guidelines before I start doing more gambling with my modest income. Please help man.
My car is a kia sportage and from what i've been hearing its no surprise to have one problem after another also being 10 years old.
Your problem may be related to either the throttle position sensor or possibly the mass air flow sensor.
Check the plugs when u remove them to see if all contacts are fully forward in the plug; the wires may recess inside the plug and not make contact with the sensor.
I've been hunting a ghost of my own which changes symptoms like a bad cold. I have for the first time a check engine light which gave me two codes; one is the ECM is not sending the signal to the tranny computer and the other is the tranny is not sending a response back. The TPS is listed in the codes as having not sent the signal. This unlikely since it has been replaced. I've been told that the mass air sensor talks to the TPS indirectly about the air flow. The tranny doesn't know where the throttle is while at road speed so it has essentially shut down my tranny functions. I have minimum upshift always to highest gear and no passing gear.
It is possible that the idle air control module is not working properly on your car.
If possible goto to a salvage yard and buy a cheap one off another car if u suspect it.
Im experiencing a slight jump around in idle with mine and it is surely related to the mass air flow sensor but I can't solve the problem as yet.
I wired in a new plug for it and erratic symptoms of trying to stall dissapeared.
Its a lot to think about as u can see i'm still guessing about mine. Good luck
July, 31, 2006 AT 12:17 AM
Sounds more like an overheating problem or an egr system problem.
January, 23, 2007 AT 9:35 AM
Same thing happened to my 96 Plymouth Neon. Erratic idle when stopped. Worked fine when driving. I replaced the EGR valve ($65 part) and it worked immediately. It was very hard to get to, so if you don't have a few hours take it to a mechanic.