Where is the IAC sensor located at, and is it hard to change??

When my car is cold before it gets to normal operating temperature when I give it gas a let off, it will stay a 2k rpms for a minute, then it will slowly go down. Even after it is at normal operating temperature, when it goes to rev down it will go to 1,100 or 1,200 rpms, and then 1k, and then 900.

What is causing it to do that?? I have checked for a vacuum leak, but I couldn't find anything.

Don't flame me for asking this question b/c I searched for info on it, but I never can find what I need.

I'm know to much about that type of thing but my car does the same thing and my friend who has a blazer does that too. so i'm guessing it's just something cars do to get warmed up. but not too sure?

when they're cold they will hang a little higher than idle but not around 2k. you most likely have a vacuum leak or IAC problem. also check your PCV valve, it's the thinger on the center of the valve cover with a hose goin in it. if hose is leaking you can get idling problems. those things cost like 4 bucks. good place to start. replace the hose too just in case

The IAC is on the throttle body. There are to sensors on the side facing the back of the engine, the one on the bottom is the IAC.