I just put my car back together after polishing my UIM and installing an intake and aluminum ast. On startup the car used to idle at 12-1300. After warming up it slowly raises up to as high as 3k. It usually takes a couple minutes for it to go from 1500 to 3000. Vacuum is solid 500 mm hg on my Greddy boost gauge. The car is non seq and it had good idle a couple days ago. No AWS, throttle cable isn't too tight, cruise control isn't causing any problems. I checked the Factory manual and it listed some sensors that might be causing the problem, including water temp and intake temp. I checked these with my multimeter and they were in spec. I've sprayed around the UIM and LIM with carb cleaner and didn't find any leaks. So I'm stumped. Other than the high idle it runs great, boosts solid. Help me!

 

Sounds like a vacuum leak but i guess there isn't one if you sprayed the carb cleaner and didn't find one. Just adjust it with the stop screw or the other one below the throttle elbow.

 

I tried that too. Still got nothing.

 

I noticed you eliminated your AWS. If you are running a stock or reprogrammed stock ECU and you have not placed a resistor in the unused AWS connector, then your ISC will open 100%. You need to stick a 330 or 360 Ohm resistor into the unused AWS electrical connector to fool the ECU into thinking you still have one. Eliminating the AWS does not stop the warm-up cycle on its own. On a cold start, if the ECU noticed the revs aren't increasing, then it will have the ISC do the job.

 

I hooked up power fc and it did the same thing. Also, it idled at 5-600 previously.

 

I hooked up the PFC and noticed that my idle takes a while to drop to 1200RPM! after a solid warm up.

 

bump, i'm guessing its a leak on the bottom of the LIM gasket.

 

Any other ideas?