Jeep Wrangler TPS Problems

Suisse

Hi, the last year the engine just said, "DONE" and quit. I have replaced the TPS and after it was good.. This year, the same problem but only in winter.. My friend said "The TPS is sensitive to water intrusion." The Check engine is ON. The computer said the problem is the TPS.. in idle it have 3.24V and in full rpm 4.75V. My friend said "On my car it's around 0.40V at idle." What is the problem ? I don't think is the TPS maybe the thread or connector ? The TPS have a adjustment ? I am despair.. MY Jeep use a tremendous number of gas.. HELP ME PLEASE!! Sorry for my bad english.

Thank you Dave

mac24

Your friend is quite correct when he says the TPS is sensitive to water intrusion, and I think it's quite possible that your TPS has just gone bad, even though it's only a few months old.

At WOT (Wide Open Throttle) it should be at 4.49v or lower, and at idle it should be above 0.26v but below 0.95v. The voltage should increase gradually and smoothly as the throttle is slowly opened. There's no adjustment possible, but you might want to remove your TPS and check the readings again while you make sure it has the full range of movement and isn't binding at all.

A bad connection wouldn't cause the high reading you have at idle. However, just to be sure, maybe your friend will let you swap your TPS for his for the purpose of diagnosis? As long as your PCM is supplying the TPS with no more than five volts you can't damage his one.

Oh by the way, your English, and obvious understanding of capitalization and punctuation, is more than good enough to have easily explained your problem.

Suisse

Thank you for information and about my english I have an other question. My father is electronics engineer. He said "I am absolutely sure that problem is the thread or connector because in cold the thread loses expension and the problem is the ground, because the voltage don't drop." It's possible ? He has one question for you.. Where it go the thread of TPS ? Where is the ground of TPS ?

Thank you Dave and Frank

mac24

OK, I understand what your father is saying, and if the TPS was grounded through it's housing that could be a possibility (though rather a remote one).

However, it has its own ground connection. Of the three connections one is a 5v supply from the PCM, the center connection is the signal back to the PCM, and the remaining one is the ground.

The ground point that the wire from the TPS connects to should be good as several other sensors share it, and they all appear to be ok or you would have several other codes from the PCM.
It's possible that the wire that connects the TPS to ground has developed a high resistance due to a partial fracture or corrosion, but that's easy to check with your multi-meter or you could just connect an additional temporary ground wire.

While I could be wrong (when you're married you get used to hearing that), I still have a strong feeling that it's the TPS.

Suisse

Hi mac24, I have tested my wire and my multi-meter said is good! I am absolutely sure that problem is not the wire. The problem is the TPS!!! You have a very good feeling

Thank you a lot for your time and your quick answer!!
Thank you again Dave :shades:

mac24

You're welcome.

taz1973

My Jeep is throwing 3 codes on personal hand held computer reader,:p0108,p1297,p0121. The problems started when I changed my water pump, I had to take it to my mechanic and have him realign my manifold gasket, he told me to change my distributor, so I did. I have 180,000+miles on my motor, I've changed my MAP sensor,TPS sensor, throttle body gasket and the elbow for my vacuum advance. It will run for about 100miles and then throw the check engine light, before it throws check engine it will start to sputter like a mis fire and then at 3,000rpm it cuts out on the throttle and it won't idle. The dealership wants me to have them diagnose it and they also think that my ECM might be bad. I have had it with my baby but I won't get rid of it, please help!

mac24

Before going any further, can you confirem it's a '97?
The '97 shouldn't be giving 'P' codes, they should be simple two figure codes like 31 or 64.
The '97 differs from later models in that it uses a version of OBDI which is unique to its model year; later vehicles use OBDII which does generate 'P' codes.

taz1973

The strange thing about my 97 is the tps i put on is for a 95 the one the dealership give me didn't fit so i took the stock one that came off of my jeep and that is how i discovered that it was a tps for a 95

mac24

It's supposedly a '97 that produces '98 and up OBD codes, although the engine may be from a '95, and it started producing these codes after you changed the water pump which apparently required the realignment of one of the manifold gaskets and a new distributor?

I guess I'm a bit lost on this one. :confuse:

Suisse

Hi Mac24, since about days my jeep starting after 3 minutes and +50 tries turn on the key :mad: .. I think it's the starter.. The battery is new.. I hear the fuse contact ! It's possible that problem come from solenoid ? Wire ? Starter ?

Thank You Dave

mac24

If I understand correctly, it takes many turns of the key before the starter turns, although you can hear it click each time?

The solenoid is integral to the starter and can't be replaced seperately, so if the problem lies with the solenoid or the starter a replacement starter is required.

It's also possible that you have a bad (high resistance) connection at either of the battery connections, the starter connection, or the engine ground.
That would be where I'd start my checks, and if that's the problem it'll be a lot cheaper than an exchange starter.

Suisse

Thank you for reply Mac24. Today in the morning my jeep have again this problem.. 10 turn on/off key .. midday Ok and after school Ok I think the cold create problem.. The battery connections is ok I will check the rest soon.

& About the TPS the problem was the TPS I have replace this and everything is ok
Thank you Dave

mac24

Glad to hear you've fixed the TPS ok.

bezzer344

Hi,

So after giving my Jeep a tune-up, and a new water pump, i noticed that when driving it at a certain point in the throttle it would sputter and buck, if you if will, but would stop both sputtering and bucking if I either let off the throttle or gassed it a bit more. So it was then hooked up to a computer to see what the problem was and it turns out that the TPS was the problem. So I went to a local parts store(NAPA) and got a TPS, installed it, and when I started the jeep the rpms went went up to about 2100 rpms and idled there. Thinking/hoping that the problem might be because it was not an authentic mopar part, I went and got a TPS from a dealer and still it does the same thing: starts and goes up to 2100 rpms and idles...

Any ideas as to what the problem may be???

Thanks,
Dave

mac24

As this started after you did the 'tune up' it migh be worthwhile to go back and check over your work. Most likely cause is a disconnected or split vacuum hose.
You can also do a basic rest of the PCM by disconnecting the battery for ten minutes.

It's also possible you have a problem with the IAC (Idle Air Control) motor, or the inlet passage to it. You may even find a cleaning of the throttle body and the IAC passage will do the trick.

huskycountry

I see you mention a PCM on this post. I just had my 07 Sahara in the shop and that is what they said they replaced, my OBD light was on that is why I took it in. When I picked up my car the techs and advisor were all gone, Can you tell me what excatly a PCM is and what it does in plain english so a girl can understand it?

roadburner

PCM= Powertrain Control Module- it's the computer that operates the engine and-if fitted-the automatic transmission.

erickpl

And I believe it is warrantied up to about 80,000 miles since it is considered part of the emissions systems.

-Paul

bezzer344