Check Engine Light

Today i was driving down to long beach from LA a annoying long drive. Traffic was horrible and the temp was 100+F. On my way back i was going about 75MPH on the highway and i felt some engine hesitation, kinda like a miss. The check engine light came on and the engine drove considerably hotter the rest of the way (didnt overheat but hot- i had to turn off AC). I also noticed the tranny shifted funny , which i think was the cause of the heat possibly.
When i got home i checked the codes and i got code 24 , TPS voltage code. I got this code last week also as i started the jeep in the morning and it almost died on me, i cleaned the connector when that happened and i thought the problem was gone. What i find funny is that i replaced the TPS and IAC with napa parts about two months ago.

any suggestions

check the fuel pump.

Check TPS and TPS circuit with a meter. Check for dead spots in voltage output and any possible connection problems.

Kyung

Well the TPS sensor itself i dont mind replacing with a OEM part this time, but how does one go about checking the circuit itself ?
Its a 94XJ 4.0 / AW4

Thanks
pete

jeepsrock said:

Well the TPS sensor itself i dont mind replacing with a OEM part this time, but how does one go about checking the circuit itself ?
Its a 94XJ 4.0 / AW4

Thanks
pete

Click to expand...

What I meant was to check the wires for good continuity with an ohmmeter to make sure you don't have any frayed/cut/chafed wires. Good idea to wiggle the wiring harness while checking cause it could be intermittant.

I take it you don't have a FSM right? There is a way to check output voltage of the tps. Basically, you're looking to see that the tps output voltage increases smoothly from no throttle to WOT. The range is 1 volt or less at closed throttle and at least 3.6 volts at WOT (check with ignition on, engine off). The signal wire in the orange with the dark blue stripe on the tps connector. Check voltage between that and a good ground.

Kyung

EDIT: This info is from my '95 FSM, but it should be the same for your '94.

Thanks for the suggestions...Here is what i have done in the mean time. I have gone to the dealer wanting to purchase a new TPS (bc all the ones from napa die in a month or so) and they wanted 75$ for it. After searching through a few mopar online sites i was able to get it nearly half of that. It should be coming in the next few days or so.

The funny thing is that after a few days the light went out (after it came on with current sensor) , but the jeep is very irratic with its driving. Sometimes since it will-
1. Turn it on and it will idle about 1500 RPM
2. Engine will stutter in specific RPM range (no cel light)
3. Tranny shifts hard and at strange points
4. Overdrive comes too soon and tranny seems to be getting a bit hot.
5. Engine seems very week.

Can this all be really caused by that stupid TPS sensor.. ??

bump.

Yes those are all a bad TPS symptoms.