Diagnostic help?

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DoctorPhate

Guest
I've been trying for over a week now to diagnose and fix this issue I'm having with the Jeep and I've completely run out of ideas as to what it can be.

Basically I just had a buddy change my clutch, master & slave cyls and since then I've had issues with my TPS. It was bucking quite heavily and the check engine light came on when I got it back. I did the three turn of the key trick and got the code for the TPS and I replaced it. Like an idiot and in a rush I didnt disconnect the battery...
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DoctorPhate

Guest
As in Crank position sensor? I'll take a look tonight.
 
mucovich

mucovich

Till Valhalla!
This is sort of an issue i recently went through - it ran like crap when i would rev it - codes showed up saying the TPS was bad so i replaced it and it ran even worse. So heres what i discovered (this may very well not be your problem though) the TPS and clocking ring in the steering wheel (the contraption that allows you to turn the wheel and not have the airbag wires and horn wires get twisted up) are on the same circuit - so if you clocking ring has shorted out (mine because of water) it will cause the vehicle to run like crap and throw a TPS code. In the end instead of replacing my clocking spring (which requires a complete disasembly of the steering colunm) i removed the multi switch and disconnected the airbag and horn connections (i don't need signals, horn and no longer run airbags) and it ran fine.

If you have replaced the TPS (i have never disconnected the battery to do that) with no luck and the codes say it's still a bad TPS then you require a new clocking spring.
 
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DoctorPhate

Guest
mucovich said:
This is sort of an issue i recently went through - it ran like crap when i would rev it - codes showed up saying the TPS was bad so i replaced it and it ran even worse. So heres what i discovered (this may very well not be your problem though) the TPS and clocking ring in the steering wheel (the contraption that allows you to turn the wheel and not have the airbag wires and horn wires get twisted up) are on the same circuit - so if you clocking ring has shorted out (mine because of water) it will cause the vehicle to run like crap and throw a TPS code. In the end instead of replacing my clocking spring (which requires a complete disasembly of the steering colunm) i removed the multi switch and disconnected the airbag and horn connections (i don't need signals, horn and no longer run airbags) and it ran fine.

If you have replaced the TPS (i have never disconnected the battery to do that) with no luck and the codes say it's still a bad TPS then you require a new clocking spring.
Click to expand...

Thanks man, thats a good lead for me to check into.

The main piss off for me is its not throwing any codes at all. The ECU thinks theres no problem. I started last night checking every electrical connection and filling them with dielectric grease. I've had a few people mention thats your best bet. I havent had a chance to crawl under and take a look at the crank position sensor but after being stuck in that damn clay last week I'd say thats a damn good possibility.
 
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Lil Warlock

Guest
I just had similar symptoms with the wifes Grand. The motor had been replaced, and it ran good for about a week. Then it started stalling, bucking, irratic rpms. No codes.
I checked all the connections (cleaned greased), thinking maybe it was a loose or dirty one. After several days of pulling things apart, I thought maybe the CPS was loose. When I checked, it was tight, but a cable had been rubbing on the top of it and wore through the wire insulation enough for it to short intermitantly. Changed CPS, no more problems.
May not be your problem, but it was the last thing I would have thought of. Oh, wait, it was the last thing. LOL
 
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DoctorPhate

Guest
yeah im in the process of greasing every fitting and inspecting wiring today. CPS is on the check list although it sounds a lot like its a fuel pump from the research ive done.
 
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DoctorPhate

Guest
I inspected all the wiring, put di-electric grease in every joint and checked the see if the Crank sensor wires were melted and shorting. Everythings all good. I took it for a drive and its still bucks however it failed to start a few times until I put my foot on the floor basically and started it then she fired up. I was sure at that point that it was fuel pump, however.... Now I've got a check engine light.. Code 14, MAP Sensor. So my question is... do you guys think its ACTUALLY the map sensor? I was going to go pick up a couple from kenny upull, at 9.99 why the hell not.

If you guys are unsure I'm going to pick up a fuel pump aswell.
 
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Lil Warlock

Guest
The Chrysler MFI were notoriuos for MAP sensors from the mid 80s to mid 90s. They would either starve for fuel or flood. Usually the later. Chances are, if it calls for MAP sensor... it is. Try one first. If you are gonna try a used one, make sure you try a couple. Finding a really good one used can sometimes be a chore. Remember that the MAP and Oxygen sensor tell the comp how much fuel to deliver. If either one are telling it the fuel mixture is too rich (even if it's not) the comp will starve the engine. Same works in reverse.
 
2

2Greys

Insert title here
Club Member
Probably stupid and you did say you checked Electrical but did you check your battery terminals? I had issues at one point with surging and taking a while to start. Ended up being a cracked battery connector.

Also X2 on what Marek said. That was the first thing I thought of. If you disconnect the clockspring and it goes away it is probably that
 
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DoctorPhate

Guest
2Greys said:
Probably stupid and you did say you checked Electrical but did you check your battery terminals? I had issues at one point with surging and taking a while to start. Ended up being a cracked battery connector.

Also X2 on what Marek said. That was the first thing I thought of. If you disconnect the clockspring and it goes away it is probably that
Click to expand...

Yeah I ripped apart the dash to replace the fuse on the back of my stereo and at the same time I tore apart the steering column and inspected, it still looks good.

As for the battery terminals, the battery itself is brand new, put it in when i bought the vehicle and the connectors were all cleaned. I even put some di-electric grease in there. I went a little crazy with the stuff lol.

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Thanks Warlock,

Im heading to kenny upull and I'm going to rip out 3 or 4. for $9.99 I'd be stupid not to.
 
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