Before I had any of these symptoms I had been splashing through a river at high speeds. Not the smartest thing but it was fun at the time. Now whenever Im driving my TJ it cuts out when cruising anywhere between 1800 to 2500 RPM. I checked the engine bay and intake for any standing water, made sure battery connections were tight, not sure what to do next. Also the alternator sometimes reads below 14 and sometimes drops to zero. I shut it off and re start it to get it spinning again but its driving me crazy how I can't just relax and drive it I always have to be shutting it off and revving it up to get the alternator going again. Could the alternator be the cause of my problem? Ideas?
Cuts out for no reason
- Thread starter Sully
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Bounty__Hunter
Super Moderator
Could be the alternator, but also sounds like the throttle pos. sensor. Do you get a check engine light?
also what yr is your jp? I have a 95' and am starting to see the wiring harness start to dry up (for lack of a better term). I have had 2 plugs already go bad this year and am starting to suspect another. The wire's are breaking at or in the plug. (TBS-MAT- and maybe temp also) Yours being a tj probably still has a few yrs to go before anything like this but just a thought.
mud4feet
New member
Yeah....and what happened to the CJ????? You really have to log on more often!!:lol: :lol: :lol:
It's a 99 TJ. Last time it got wet was almost 2 weeks ago and there is no sign of water under the hood. Check engine light is on it backfires every once and awhile. Almost feels like it's missing. Still have the CJ but I cant get to work on it until I have the TJ all sorted out.
Bounty__Hunter
Super Moderator
What trouble code is it throwing?
TwistedCU
New member
Most chain-type parts stores like Autozone or Advance Auto will scanit for free and givew you the code.
mud4feet
New member
Or you can try the ol' "key-on-3-times" method (if it's like my TJ). If memory serves (I haven't done it in a while, but there's a thread on here somewhere about it), you hold the odometer button down, swith the key to the "start" position 3 times, then let go of the button. It'll shoot you the codes on the odometer.
TwistedCU
New member
mud4feet
New member
Might be this method:
http://www.offroaders.com/tech/jeep/TJ_diagnostic_codes.htm
Don't know.........yours is an earlier TJ............I'll keep searching.......
http://www.offroaders.com/tech/jeep/TJ_diagnostic_codes.htm
Don't know.........yours is an earlier TJ............I'll keep searching.......
mud4feet
New member
No help, but an interesting site, none the less:
http://www.geocities.com/jeepboy49028/changes.html
another reference here:
http://www.visi.com/~tam/tjfaq/sec4.html
http://www.geocities.com/jeepboy49028/changes.html
another reference here:
http://www.visi.com/~tam/tjfaq/sec4.html
Last edited:
Bounty__Hunter
Super Moderator
If the guages go through their self-test, you released the tri reset button too early. Push and hold the trip reset, turn the key to run and back to off before releasing the button. This may show codes.
P0123 Throttle position sensor input above the maximum acceptable voltage.
P1391 Intermittent Loss of the Cam Position Sensor or Crank Position sensor has occurred.
Bounty__Hunter
Super Moderator
Sometimes replacing only one of those two could fix the problem, a sensor will occasionally have a domino effect and throw other codes. I'm guessing the throttle pos. sensor, but who knows.
redrooster
New member
I assume the TPS would be the easier of the two to swap. So you might try it first. Unfortunately, it is a lot less likely to have gotten wet. I believe the Crank Position sensor is in your bellhousing. I don't know how you access it. It would have been a lot more likely to have gotten wet/muddy. I can see where the CPS could be sending a false signal to the computer (tells it you are running less RPM than you really are). The TPS tells the computer how much throttle you are giving the engine. Low volts means low throttle high volts means it thinks you are giving it lots of throttle. One is likely confusing the other.
Two things you might try: Reset the computer...I'm not sure if removing the battery cables will do it on a TJ or not. The other is try to get at the CPS and clean it.
Good luck.
Two things you might try: Reset the computer...I'm not sure if removing the battery cables will do it on a TJ or not. The other is try to get at the CPS and clean it.
Good luck.
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