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Wide open at start up

DieselAirman

NAXJA Forum User
Location
SW Michigan
Rainy and cold in MI today, normaly keep the XJ in the garage but thought I would leave it out overnight to wash some of the crap off. Got in it to go to town and turned the key on and she wound up wide open. Shut it off and tried again, same thing but it would respond to the throttle, but it would only go higher, not slower. Some thing on the third try. Thats when I thought Id better talk to you guys. Its a stock 99 with a BB and SYE. Any ideas?Thought I might try resetting the computer.
 
DieselAirman said:
Rainy and cold in MI today, normaly keep the XJ in the garage but thought I would leave it out overnight to wash some of the crap off. Got in it to go to town and turned the key on and she wound up wide open. Shut it off and tried again, same thing but it would respond to the throttle, but it would only go higher, not slower. Some thing on the third try. Thats when I thought Id better talk to you guys. Its a stock 99 with a BB and SYE. Any ideas?Thought I might try resetting the computer.


how many miles on your rig? my Jeep did that when it had a bad throttle position sensor? that could be your problem. I believe autozone can test the TPS, if you have one near you. But, if it idles high at every start up, that might not be it. hope that helps some.
 
My TPS is going bad on my '87. This morning it was wet at my house too. It was idling a little high too but I didn't have that problem. Coincidence...:dunno:
 
Hood vents?

I had this problem when I got back from overseas. The Throttle body had corroded and was sticking, the spring wasn't enough to return it to normal.

check to make sure the throttle plate is moving freely by hand, then if you still have problems check for a VAC leak or unplug your IAC to see if that helps.

If you still have problems, remove and clean your throttle body and IAC.

If you still have problems and you are sure the IAC is functioning properly....air is getting into the manifold somehow, either a bad gasket, cracked manifold, open vac lines, etc. find the leak and repair accordingly.
 
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