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Wallyman
September 9th, 2003, 17:47
About 30 % of the time i start my engine, i get a racing situation where it sits at 3grand.sometimes it'll drop 2 idle after about 30 secs.otherwise i need 2 shut it down and hope 4 a good start next time.I have recently replaced the Idle air stepper motor.while attemptimg 2 solve a different problem.Kinda bugs me. any suggs?
dvsjoker
September 9th, 2003, 17:53
wow i came here to post the same issue. my jeep does the same. it some times just idles at 1500 while waiting for a light or on park if get the answwer let me know i changes the tps and the idle sensors i been told it mite be the egr valve but how u test that anyway let me know
Wallyman
September 9th, 2003, 18:36
What year is your XJ? Well as far as the EGR i donno. seems almost like there is a vacuum issue.My PCV has been broken off about a year now and i thought it might have an effect(long term type) on things. I'll let u no ...
XJMark
September 9th, 2003, 18:38
Mine occasionally has a dirty connection on the Idle Air Controller plug causing the same thing. I just unplug and re-plug it a couple times and it's fine. I think I'll put on some dielectric grease to prevent corrosion on the contact pins. It seems like the problem gets worse after it rains alot, it must be some type of corrosion due to condensation or high humidity.

HTH,

Mark
MJmk
September 9th, 2003, 23:40
On my '87, the high idle has always been some kind of dirty connection issue. When it was idling high, I popped the hood and wiggled the wire connectors one at a time until I found the one that slowed the engine down. So far I've cleaned the TPS connectors, and the C101 (that big one behind the brake booster only '87's and '88's have) connector. I sprayed the connectors with electric contact cleaner and put a dab of dielectric grease inside before snapping them together. Cleaning the C101 is kinda pains-taking and nasty, it's filled with some tar-like grease(?) that you have to carefully scrape out before the cleaner and dielectric grease treatment. If you have a problem with the C101 connector, try torquing the center bolt to 70 INCH pounds first before taking it apart, and see if that improves the connection.:)
Wallyman
September 10th, 2003, 04:11
Cool, mines an 89 so i guess i dont have 2 worry about that nasty 1 u r talking about. however i think i will go n that direction. Thanx guys, i let u no how it comes out