When the car warms up to normal temp the idle drops to about 475 (which is too low I think) and bobs just a tad. No biggy. When I put the AC on the Idle will stuble and almost stall before it catches itself and revs a little. My base timing is around 4 and my mods are in my sig. It almost seems like I have a vacuum leak but i cannot find one. I had one before and it took me forever and a lot of money to fix. Could my IAC need to be adjusted?