This sound like a faulty TPS?

[89Jeep_guy]

Ok my 89 has had a few issues over the past months. First and formost, the Jeep goes through gas like its water and before anyone suggests a tune up all the obvious has been done (air filter, fuel filter, plugs, oil change, tire rotation etc.). Also it has a very odd issue with lack of power. Say your sitting at a light and you go to step on the gas it bucks and the rpms drop bad before the car finally catches up and goes. Occasionally in the same scenario the car shuts off. I can restart it with no problems though. From what I understand TPS sensors can be a big culprit of this so I'm wondering if this is what I need to check. I will mention that I replaced majority of the vacuum lines and the vacuum harness itself. Any suggestions or thoughts?

[Trooper]

Coolant temp sensor is the root of all evil. check the connector for ANY corrosion.

[sreppok]

Originally Posted by Trooper

Coolant temp sensor is the root of all evil. check the connector for ANY corrosion.

For that matter:

Throttle Position Sensor
Crankshaft Position Sensor
Collant temp sensor
knock sensor


Find the locations of each of these. I know the CPS is on the rear of the engine, above the valve cover.

These plus are terrible for corroding, or just plain being bad contacts. Un plug, inspect for dirt, debris, corrosion, melting. Clean if necessary, use White Lithium grease if you want to. PLug back in, unplug, and replug at least once more.

Try starting again. The unplug-replug method works well, mine needs it every three months on CPS. Soon, I will just replace the sensor.

[littleblackxj]

That doesn't sound like a TPS problem. I'm thinking you have a couple things wrong here, and most likely a vacuum leak. I would check your o2 sensor, air temp sensor and map sensor.

[89Jeep_guy]

I did a little digging around and didn't find any vacuum leaks. However the ends of the hose that comes from the rear of the valve cover that plugs into the elbows are covered in oil. The car has also started valve knocking, I'm not sure if this has anything to do with the low idle and hesitation I'm experiencing.

[shortbus]

im getting the same deal in my 96 right now, im changing out my MAP sensor saturday and ill let you know how it works out!

[islandbum]

Originally Posted by Trooper

Coolant temp sensor is the root of all evil. check the connector for ANY corrosion.

I agree with the coolant temp sensor, but only as part of the problem.
I had similar problems with my jeep and the tps was bad also. Doesn't cost that much to replace them both and well worth it.

[swells6367]

my 90 does this. I do a computer reset and it fixes it for a long while. I have replaced every sensor and there was no real difference until I read about the reset..

[shortbus]

^ care to elaborate on said reset?

[littleblackxj]

Reset the ECU. Unplug the positive lead on your battery, turn the key to accessory, apply the brakes twice, turn on the head lights twice, turn off your head lights, turn your key off and reattach battery cable.

[shortbus]

ohhhhh ok thank you!