What's up guys, I was wondering, my car still has it's idle surge and I have replaced the isc and the ecu and blocked off the egr. All I have left to think of is a vacuum leak. Is there anyway anyone could tell me how to check for a vacuum leak and which lines I need to check for that. Also, someone told me something about a idle air control circuit, I was wondering if anyone knew what that was and if you could tell me where it is how to test it, or if it's what I have already checked. Thanks to everyone.

 

did you try replacing the iac?

 

What is that? I replaced the ISC if that's the same thing. It was on the TB, under the intake hose elbow.

 

did it have a square like connector?

 

Yup, with 6 prongs in it, and it has like a punger thing on it that goes in the TB and is supposed to move in and out. Mine doesn't move in and out though, so I'm wondering if there might be a problem with the wiring? I took it out and watched it, and had someone turn the key from acc to on without starting the car, and it vibrated but didn't go in and out, both of the ones did it, the one that I had on there in the first place (a black one) and the one I replaced it with (a brownish one). I've noticed that it's worse when it's cold, when I first turn it on when it's warm, it idles up to about 2,000 RPM for a couple seconds, then start surging from about 1200-1500 RPM at a slow steady speed. When it's cold, it idles up to about 3 to 3500 RPM and stays there for about 10 seconds maybe, then starts surgingat a fast and not too steady speed. So I'm wondering, could it have something to do with the FIAV? I'm almost out of options. Thanks.

 

tps

 

Whats the tps? And where is it located?

 

get a can of eather (starting fluid) and spray it around your vaccume hoses & intake manifold. If there is a vaccume leak, the engine will bog down, and you will know what area to look at more closely.