High idle can be caused by several things, the Throttle Body might need cleaning, the Idle Stepper might be bad, or the Throttle Position Sensor (TPS) could need replacing. However, it may be something you can easily fix without spending any (much) money on the un-necessary replacement of expensive little components, so you should try this first. I cured my high idle by merely cleaning the connector on the TPS. It is suceptable to moisture, oxidation and corrosion, and even the slightest ammount of either, can send false information to the computer. This can be tested the next time you experience the high idle. While it is reving, open the hood and wiggle the connector, sometimes this is all it takes to make the idle drop to normal, if it does, then the connector is not making good contact and needs to be cleaned. If the idle did not drop by wiggling the connector, try unplugging the connector, and see if the idle drops. If it does then the problem is either the connector or the TPS itself. In either case, try cleaning the connector first (that's cheaper than a new TP$). If wiggling or removing the TPS connector does not drop the idle, then it is likely it is the Idle Stepper, or Throttle Body, but those items are not in my knowelege base (yet), so I can't help much in that area.
The pins of the connector are small and difficult to clean, so a dental pick or small jewlers screwdriver will be necessary to get in there and clean it. It is helpful to use an Electronic Parts cleaner (available at Radio Shack) to help flush away the contamination as you scrape the contacts. After you have cleaned it as best you can, apply a small ammount of Ox-GARD to each pin, then work it in by plugging the connector together repeatedly. Now unplug it and wipe away any excess and give it a try. This approach cured my intermittent high idle problem, and it has not come back in three years!
Back to Tech Page Back to Electrical Page Back to Jeep Page
A Wizard of Wiring