Hi, I'm new to the forum, but have researched my problem here without a solution so am hoping for some hope. I have a 1998 Cherokee XJ Sport, two-door, 4.0 liter, 5-speed manual, 123K miles. It runs well and idles well, but will not drop to idle while the vehicle is moving. I have installed all new sensors on the throttle body, a new vehicle speed sensor and had previously replaced both O2 sensors.

If I am sitting parked and rev up the engine, it drops smoothly to normal idle. However, if the vehicle is moving, whether in neutral or in gear with the clutch in, it will hold the idle at about 1100 rpm. As soon as I stop, after about a five second delay, it will drop to normal idle.

I am ready to tear my hair out and I don't have any to spare. As I mentioned, I have read all of the threads here and on the net about improper idle, but none seem to address this issue. I would appreciate and thoughts or ideas on what might be causing this phenomena. Thanks for your help, Joe