My car has had idle issues ever since i got it back together. I think i've tracked it down to what... but i still don't know why. For some reason after i drive for a while my air idle control valve will open, and stay open. Resulting in a 2k+ idle.

If i start the car after its been sitting for a while, it has a nice ~700 rpm idle. If i go drive it and stop we have a 2k idle again. It did this before i installed my power FC, and still does it afterwards. I've searched, checked everything i can think of... and still nothing. Any help what so ever at this point will be much apprecaited.

 

Oh, and to answer the questions i see comming. Drives fine, cat removed, 99 spec turbos, pfc. TPS is within spec... screw below the throttle body has been played with non-stop.

 

I have the incredible shrinking throttle cable.....which caused high idle conditions.

Check your throttle cable and make sure it is not pulling the throttle open due to sticking, movement, peddle issues, etc. I ended up putting slack in the adjustment to compensate for the fast idle cam and other things.

 

I've got similar problems. I'm still trying to fix this stupid problem. Except, when I start my car, it idles at 3k. If I drive around, it idles at 3k. Oh well, I need a day to pull everything apart.

 

There is a post on cleaning the IAC that might be your problem. Plus check ohm's to see if its in spec.

 

can you check what the throttle % says on the PFC? i'd imagine having a standalone EMS would make idle issues a cakewalk.

 

Guess i'll be ripping it apart this weekend.

Jacob, you are more than welcome to come over and bash it with a hammer with me when you come to get my old turbos.

 

You can remove the ISC easier than you think. You need to locate it first on the back side of the UIM, just past the throttle body. The ISC is mounted with two 10 mm nuts. Unplug the ISC. Use a 1/4" ratchet with a short extension and a 10 mm socket to remove the nuts. Try to remove it with the gasket in tact or you will need to clean off the remainder before remounting.

 

cant you disable it with the PFC?