My 92 SE mostly idles at 1000 rpm.....and when I strat it when cold....idles at 1200...and drops to 1000 in about 10 to 15 seconds....when it used to idle at 1500 when cold for a couple min and slowly drop to 750 idle...is this a bad 02 sensor????

 

Hmm My car ususally idles @ 1000 rpm if I'm in Park, in drive it idles @ 700-800 rpm...what gear are you in, and when I start my car it idles @ 1500 rpm and drops to 1000 in about 4-5 minutes..

 

An intake vaccume leak is what id check for first..that can make it idle high..check for a hissing sound from any vac hoses under the hood.

 

Yeah, check the vacuum lines for leaks or disconnections. Typically though when there is a vacuum leak the rpm's tend to "hunt", meaning the rpm's will fluctuate from high to low. When was the last time you worked on your car? Possible u accidentally disconnected a vacuum line like I have (off the intake manifold). Possible tune up time! Check all the simple things before going with the last resort of adjusting the A.A.C Valve (idle speed. Good Luck!