seems my car is searching for a idle when its cold, what temp does the ecm have the iac hold up the idle? also when its warm idle hangs hi for a minute or so then comes down to 700rpm on my digital tach on my timming light. car is a 91 rs 5.0 tbi with manual trans and no mods.

 

That sounds normal for warm operation. You can always clean your IAC, its a good place to start.