Idle Problems driving me crazy

[BubbleBrad]

Okay, my car used to die on sharp turns and sudden stops. Took care of that problem (EGR Valve). I thought that would take care of this problem. but no luck. With the car on, in park, the engine revs up and back down on its own. On the way down, the engine shakes, as if it was about to stall, but it doesnt. So, the rpms go up and down on its own until the car is put into gear. It wouldnt really worry me, but the way the motor shakes when it revs down is cause for my concern. I remember a mechanic pressed something behind the throttle body, I think, that made the engine rev up(what was it)? Anyway, when he did this, the engine shut off and wouldnt start back up. In order to get it to start back up, I had to pump the gas as I turned the key, and continue to pump the gas to keep it from shutting off. I know a little about cars, so if anybody else has had this problem, any knowledge or suggestions would be greatly appreciated. Thanks.

[CD Smalley]

Need the details please... year of car, engine etc....

My guess is your IAC needs cleaned, or replaced.

[BubbleBrad]

'91 5.0 305

[BubbleBrad]

Anyone? Is there a way to check the IAC without taking it to a mechanic? I also motice that sometimes while im a redlight with my foot on the brake, my car surges foward, as if it was going to take off, even with my foot on the brake.

[RageCage]

Originally Posted by BubbleBrad

Anyone? Is there a way to check the IAC without taking it to a mechanic? I also motice that sometimes while im a redlight with my foot on the brake, my car surges foward, as if it was going to take off, even with my foot on the brake.

You might be able to remove the IAC valve and clean it out. That worked for me, with my gf's Sentra. I removed it, I sprayed some carb cleaner into it, and got a lot of junk out. They get gummed up and carboned up over time, because the intake gas mixture gets into them somehow. Fixed the problem.

Your surging does indeed sound like an IAC problem. Somebody else verify this, please, but you could also disconnect the wire to the IAC and see if anything changes.

When you put the a/c on does the idle get low? The IAC is supposed to bump up the idle with the a/c on, I believe.



Rage