Sticking Throttle

Well My jeeps throttle is sticking.

96 XJ Auto 99k 4x4.

I have a bored out throttle body made by trail rate this (a member in the SE Chapter)

Last year the Idle Air Control Valve was replaced with a napa part. I took the IAC out this year went to clean it and it wasn't dirty at all neither is the throttle body. I reset the computer and tried it again, still same problem. Now Im scratching my head. I drive around it wont stick all the time just sometimes. If I tap the gas real quick it will unstick and rpms will return to normal. I can usually tell when Im braking as it will fight me but I am able to stop, the motor is just running high on rpms.

Any thoughts or ideas?

I was thinking my next step would be to go get a stock throttle body swap it out and see if its just in modifications trail rate this made to the throttle body.

Is the cable binding, or is it the TPS? A bored TB still closes. If it's intermittent, I'd test the sensor.

Any suggestions on how to test either of those?

Try to isolate each component individually.
Disconnect all cables from the trottle body and check to see if it return to the stop every time it is opened by looking into it with the air cleaner hose off and engine off.
Check the trottle return spring to see if it is weak, broken or missing.
Check each cable that is attached to the trottle body for smooth operation/retraction when it is extended.
And most unlikely, but check the gas pedal for binding.

I had a similar issue recently. And the return spring "housing"? on the cable was broken. I have temporarily fixed it with zip ties.

Hmm all sounds like good stuff to check i will definitely look into it more this weekend if possible.

I'm having the same issue with my '96. i had the computer 're-flashed' almost two years ago, as per the factory recall. Since then, I'm on my fifth TPS, and just now it seems to be behaving. It'll still continue to gently pull after I let off the gas, but it will settle down to a reliable idle after a few seconds. The original went a few months after the recall, as I was climbing a long grade on the Interstate. The engine barely skipped a beat, but the CEL came on. When I got home, the scanner said TPS, so I went to the junkyard and got a 'new' one. At that time, I completely disassembled the throttle body, and gave it a thorough cleaning. This lasted about a year, then the throttle started running on. I bought a brand new Standard brand TPS, and it was horrible from the word go. Back to the yard, home with three more. One lasted about a month, another was OK, but the one on there now is the best of the bunch. I lined up all the TPSs I had on the bench, read them all with the multi-meter, then compared these readings to my '92, which behaves perfectly. The TPS in the '92 had the lowest reading of all, and I chose the one with the second-lowest reading to install, and it seems to have worked. The tranny was acting up too, when there was a marginal TPS installed, as it would hunt between gears, shift funny, and the torque converter would lock and un-lock at odd times. Now it's behaving just fine!

I would suggest getting a handful of them, and read between two of the contacts to find the one with the lowest reading (highest resistance) between the two of the pins that change as you open the throttle. If you're convinced that the problem is not mechanical, then it's time to some electrical research.

heyhar said:

I'm having the same issue with my '96. i had the computer 're-flashed' almost two years ago, as per the factory recall.

Click to expand...

I was absolutely not aware of this! I wonder why I did not receive a letter or anything of the sort with that recall. Do you know the reason why the recall was made? I guess what im trying to ask is what was the problem that was happening for them to recall and get the comp flashed?

IIRC, I received the recall in '08, and I sat on it awhile, as I was working a lot. I got it done in June of '09. I was initially hesitant to have it done, as I had seen a few complaints on about folks having problems afterward.

The recall, according to what I've seen, involves the re-flash and a visual and 'rattle check' of the catalytic converter. The ceramic honeycombs were breaking up, rendering the cat useless. Well, the cat was fine, other than the heat shield rattling, which they won't cover. The cat on our '95 sounds like a bag of marbles.....

I recently asked the dealer where I had this done if they'd had any complaints, or what was involved, and they said 'No, and we don't know'. Great!

I'm thinking of heading to the junkyard to hopefully find a virgin computer, if it ever gets warm and stops snowing. The only downside is that '96 was a stand alone year for a lot of electrical and emissions equipment, and no other year computer will work. If your vehicle was done by a former owner, there should be a sticker on the radiator support with some code numbers and a date. Both of our '96s have them. Or, you can go to any Chrysler dealer, and they can tell you if it's been done. I don't know if I'd recommend it, though.