You posted in the F series section, but essentially their the same beast. Because the problem occurs after operating temp (+-195F), the computer is in closed loop function & should have a continuous memory error code(s) stored in the KAM (Kept Adaptive Memory). Run a scan for Error codes. Also what year? If I Had to take a wild guess ...................(drum roll) Throttle Position Sensor Circuit!.............or.............(more D.R.)..........Incoming Air Control Sensor Circuit! A Haynes Manual will give you method & specs for testing. Next could be EGR Solenoid, then EGR function but the fact that it runs in Cold Start Mode till operating temp is reached means Coolant Temp Sensor is OK. Without codes & testing you"ll be throwing parts at it till your arm gives out, or your wallet flat lines. Do it right & you can spend the saved $$'s on lotto (or maybe a K&N air intake).
Last edited by ymeski56; 04-11-09 at 10:02 AM.
Reason: Cause I felt like it.