Hi all. New to this site, so please bear with me. I have read quite a few threads dealing with idle issues, but not sure how to proceed next. I have a 1999 Jeep Grand Cherokee with 4.7 that I recently purchased from a private party. Motor runs strong & tranny shifts fine. When warmed up the motor has idle surges while in park...have not noticed the problem while driving. I first replaced the TPS (which seemed to help a little), then also replaced the IAC. Cleaned the throttle body & checked for vacuum leaks. I still have idle issues in park with engine warmed up - will idle at about 600 rpm, but surge periodically to about 1000 or 1100 rpm. Any help or advice would be sincerely appreciated...thanks!