Dodge Repair: Car Stalls 1999 intreped 2.7, star dealer, exit highway

Question
I've had to car on every computer available that a 5 star dealer has and shows nothing wrong but when car gets to full tempeture idle drops to 450 to 500 RPM and runs rough and has stalled. It stalls almost every time I come off an exit. (Highway)Car will run find until it gets to full temp.Car stalled just taking foot off gas while making a turn.I have noticed RPM bounce up and down from 400 to 700 once this starts. Also once in awhile after I restart car idle will stay up around 700 RPM.  

Answer
hello robert
what the problem when the car is on the compuiter it is runing good this is why they cant find it.

Now what the problem is a idile controll senser it will do just as you are telling me when they are bad . have it changed and then let me know . pete