idle question... classic

[ckinart]

yep, another idle question... i cleaned my IAB a few months ago, which cleared up some idle issues that i had in the past... now i have this new symptom: when i start the car cold, it behaves exactly as it should, warms up, and idles perfectly (searches a tiny bit, about 50 rpm, but hardly noticeable)... the thing is, when i shut the car off, and then restart it a short while later i.e. when the engine is still warm, it runs horribly, revving from around 600 to 1300 rpm, nearly stalling, and sputtering... usually, i just give it a bit of fuel and drive on, and by the time i hit the first stop sign/traffic light, it has straightened itself out...

i've read plenty of idle posts, and most times the answer is to clean or replace the IAB... my question is, can the IAB be affected by engine temperature? i have no problem with replacing it, but i'd just like to make sure i'm doing something constructive...

thanx in advance for any advice...

<small>[ April 16, 2002, 08:20 AM: Message edited by: ckinart ]</small>

 

[Mike Kopstain]

That definetely sounds the the IAC/B. It is a simple part to replace and should alleviate the problem. Unfortunetlely my car is currently suffering from the same problem, but I don't have the money to fix it. frown

 

[sdpatt]

Do you hear any low-pitched rumbling noises from the rear of the car (fuel tank)? That would be the fuel return line check valve getting old. But that part usually only causes a stumbling idle, not a surging idle speed.

If it is your IAC valve, and it is affected by temperature, then cleaning won't correct the problem. That would be an electrical problem and only replacing it would solve the surging. One way to check for the IAC valve causing the problem is to turn the key off then restart the engine. If the behavior changes at all, then the IAC is suspect. Shop around the on-line and local parts sources for this component as at is available through other sources than Ford.

Have you been resetting your idle programming after the IAC cleaning?

 

[ckinart]

yes, i reset the idle program after cleaning the IAB in accordance with the procedure that has been posted so many times... the only time i've ever noticed an unusual sound from the fuel tank area is during a self test (KOEO), but it sounded more like some sort of electrical actuation, about 2 seconds in duration... would that be the return valve?

thanx for the input, i'll try restarting when i have this symptom, and see if anything changes...

as for alternative part sources, us canadians have an unfortunately limited number of sources other than ford for parts such as this, but i'll look around anyway...

<small>[ April 16, 2002, 12:16 PM: Message edited by: ckinart ]</small>