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Discussion Starter #1
OK, first off I've decided I don't believe that a rough idle is endemic to our cars. There have been periods of time where my car had a very smooth idle, regardless of temperature, or whether or not the A/C was turned on. I have had the slightly lumpy idle in the past, but after putting my new motor mounts in it went away completely and I've had a good idle for a long time now, HOWEVER....

Now my car is doing this wierd thing where anytime I let off the gas the revs will drop down to around 500 for a few seconds. Then the car figures out it's supposed to be idling and the idle goes back up to 750 where it's supossed to be. It never idles low at any time except after I lift completely off the throttle. In other words it's just taking a long time to figure out how to idle right, when it is called upon to idle.

I remember someone posting about this specific idle problem before but I can't find it now. Has anyone fixed this before? Please don't guess, but diagnose. Thanks for any help guys.

[Edited by antiSUV on 05-12-2001 at 12:26 AM]
 
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You said no guess but your car is not here. So I will still guess. Maybe your idle air control valve is a little dirty or old and slow to react, or your idle port by your butterfly valve maybe clogged and your idle air control valve is adjusting to it or vacuum leak? :rolleyes:
 

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I would try this first. Disable the computer by grounding the green computer. Make sure that the car is warmed up and that all accessories are off. Verify that the car is idleing at 750.

Next the following items detect when deeleration occurs; the distributor (on turbo models) and the Idle switch that is right on the TB. These are supposed to cut fuel to the injectors when deceleraton occurs.

What seems to be happening is that the car detects deceleration, it cuts the injectors and goes to idle condition. The base idle is then used until the ISC (Idle Speed Control) can adjust.

I would check the distributor, the ISC and the idle control switch. (After you check that your base idle is good).
 

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Discussion Starter #4
Hey thanks man, I'll check it out.
 
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