bad idle on a cold start.

[brittken]

I cleaned out my throttle body and pulled my iac controller out and cleaned them both real good with throttle body cleaner.
It seemed to idle really good after that but i think the engine was still warm. Today on a cold start the idle jumped up and down almost worse then before i messed with it. Could the iac controller be worn out or is there something else i could try to fix the problem. I dont want to spend 50 bucks on a new iac if that is not the problem. Please help. Thanks, brittken

 

[Swt_86]

Don't know what chip you are running (if any) or if you have done any mods to your engine. Would help if you created a signature for your profile. If you are talking about the up and down rpm in neutral or park just after you start the car, this is standard equipment for the stock engine. I've had mine since new and it has always done that in very cold weather.

 

[brittken]

Thanks for the response. I am about 95% sure that I am using the stock chip. I had the car hooked up to a turbolink program 2 weeks ago and it read that the oxygen sensor was bad so I replaced it this weekend when I cleaned the throttle body. The car is all stock with no modifications at all. It is a 1987 turbo t with 70000 miles on it. It just seems that since i did all that work on the car this weekend the car idles worse on a cold start then before i did anything to it. However when the car is warmed up it drives and idles great. The car does seem more responsive since i did all that work to the throttle body and iac. By the way, How do you create a signature in your profile without registering all over again?

 

[Swt_86]

Just a couple of things to check. Make sure your IAC counts and TPS readings are still within spec. Procedures are here: http://www.gnttype.org/techarea/maintenance/maintpage.html

In order to change your signature, click on the User CP button near the top of the page, then click on edit profile - pretty easy.

Hope this helps.

 

[scottyb]

A modern chip will almost certainly improve your idle characteristics. I didn't have the hunt idle like you, but my Thrasher eliminated my cold stall and tip in stumble.