My '94Z starts great and idles great until I turn on the air. It immediately drops to about 450 rpms and sometimes just simply stalls. The compressor doesn't get hot, the air is cold and everything seems to be working right. The IAC isn't very old and recently cleaned. Any suggestions??

 

You probably just need to up the IAC counts some. Try cracking the TB blades open a tad more via the throttle stop.