I've got myself a bit of a problem I can't seem to figure out here, I've got a 1990 4.0 L - standard tranny that after it warms up and is driven a bit (5 - 10 minutes) the engine starts to idle high, between 2000 - 2500. I've tried the obvious, cleaning the throttle body and changing out the throttle position sensor and the idle stepper motor, when the engine is idling high, the throttle body is in the fully closed position. I can't figure what I'm missing, I would say it was a vacum line, but it doesn't happen all the time, just after the engine is good and hot.
Any guesses, thoughts or direction would be greatly appreciated,
Thx
-YJ/XJ Dan
Topic: '90 4.0 L idles high (Read 1569 times)