When I start my car the idle revs up to about 2000 rpms and never comes back down? What are the possible problems with it? How do I check for the various things that you think it is?
You could have a vacuum leak, the IAC is stuck/bad, throttle position sensor bad/out of adjustment, throttle blade open too wide for starters. What chip are you running? Do you have a scan tool?
my car started doing that when i put in the Turbo Tweak chip.. it only does it on the first couple of starts after hooking the battery back up.. it goes down to a low idle once it "learns" the operating parameters of the engine.
If it has a stock chip, ACXA,BBKJ, I would replace it with a TT chip. The stock chips are pretty outdated for today's gasoline. The TT chip will greatly improve driveability.
I had a high idle issue. One of the issues that I found wrong was that my IAC was stuck. It would not turn on the threads. I gently grabbed it with some pliers & a rag & was able to break it loose without marring it. I then lightly oiled it & replaced it. That seemed to help. The IAC housing is plastic so be careful removing it. It should only be about hand tight.
