1G Intermitent hesitation at low rpm

[spudgta]

I have a 1990 eagle talon tsi that i bought a few days ago and i am trying to fix an idle problem that is driving me crazy! I dont know the first thing about the car or where to start looking for the problem, i have replaced the plugs, wires, fuel filter, oil, and pcv valve.

The problem is it has a bad hesitation and stutter in the lower rpm range, and stalls out once in a while. The funny part is if you give it a poke it will snap out of it and return to normal idle conditions. Now when the idle problem starts the service engine light comes on and the car idles down to between 300 and 500 on the gauge but the boost stays up. Now during driving conditions the car barely gets going under its own power but as soon as i am at wide open throttle it snaps out of it and takes off like it should, i know little about this car and it is bone stock for the most part i have had it to a few people and they want to throw parts at it as usual almost 3000 worth. I dont want to go replacing a bunch of parts till i get some definate info on the car so any help would be greatly appreciated.

Thanks
Les MacDonald

 

[Codester]

Have you checked for boost leaks? Many of the new DSMs I buy always have boost leaks from either old vac hoses or bad seals in the throttle body. It may even be a bad 02 making you run really rich.

 

[haswesley]

Sounds like a fuel delivery problem at low RPMs. This could be caused by a bad O2 sensor, dirty injectors, or maybe as simple as your idle control screw. check those things first.