Ever since the motor swap, my car has had an random surging idle problem. I have a new IAC and I did the IAC adjustment procedure listed on this site and that did help, somewhat.

All my other sensors are relatively new. The problem is when I come to stop lights and my car is getting around 220* or above is when it really seems to do it. I'll stop at the light, it will idle fine for about 10 seconds, then surge and surge, till finally it surges to around 400rpm and can't recover so it will stall out. I then I have to start it back up...This is MURDER on my starter esepcially at those high of temps. Sometimes it will not crank right over, kinda budge a little. Its also very annoying because I have to press the brake pedal hard so the car won't jump forward when it surges to keep itself from dying. It seems to die quicker if I leave it in Drive and have the A/C on. When I come to long stop lights, I switch all the crap off, put it in neutral and wait till it starts surging badly, then rest my foot on the gas to keep the minimum air up.

When it is also this hot, say I press the gas a little or more then suddenly let off, 60% of the time it will just die while its moving. Very annoying.

My L03 ran worse when it was this hot, a little rougher idle, but NEVER this bad.

I know its probably a tuning problem but I don't know where to begin? This also was a BIG problem when I took the car to the track, It will stall out as I was turning to line up because you have to press the gas and let off and the car would be extremely hot...embarassing as hell.