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98 Cherokee check engine light help

EM98XJ

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The Hen that laid the Golden Legos
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Hey guys I've been having some trouble lately with my XJ. It's a 98 with the 4.0. Every few weeks my CEL would come on and it was always coming up as P0122 which is throttle position sensor. It always went off the next morning though. I replaced the TPS twice in February 2015 thinking I had gotten a faulty unit.

This has been happening for a few months, but was hard to diagnose since the CEL always cleared itself. Last week it came on and stayed on though. Checked my code and it was the same thing. Went to NAPA and swapped it out for a new one. Jeep was running fine till the next afternoon when my CEL came back on. At this point I'm thinking there must be an electrical issue. So I checked it again and these are the codes that came up.
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At this point I am lost. Electrical issues are not my strong suit. I am going to be adding an additional ground strap tomorrow, but other than that I don't know what else to try. Any advice would be greatly appreciated.
 
need to check and see if you are getting a good five volt signal to the sensor.. and make sure it will do 0 to five volts with a meter and the key on and watch the meter as you manually pull the throttle open..may have a bad wire or loose connection in the weather tight pak look into the connector and see if there is any bent or pushed back circuits..but replacing the o2 sensor is a must to prevent catalytic convert stop up and it sounds like the lead wire to the sensor may be frayed or heated wire is bad or grounded to chassis and the last is because of the first codes..
 
Our town and country minivan did crazy multiple codes. I was swapping parts like crazy. FINALLY found a forum that mentioned he wiring harness touches the engine and melts all the wires together. That was it. I stripped the mess apart and taped it all up.
Hope this maybe helps. And yeah check frame and engine grounds.
 
I will have to check on that. Would that cause all these other codes as well? I doubt the o2 sensors are already bad. I replaced both sensors with Bosch replacements in March 2014.
 
Our town and country minivan did crazy multiple codes. I was swapping parts like crazy. FINALLY found a forum that mentioned he wiring harness touches the engine and melts all the wires together. That was it. I stripped the mess apart and taped it all up.
Hope this maybe helps. And yeah check frame and engine grounds.

That is crazy I never would of even thought to check that. I have checked several forums and have not seen anything that had all those same fault codes unfortunately.
 
I really hope not. Guess I should look into price for a rebuild. Any recommendations for a shop near Cumming? I hope it's something simple as I'm a little strapped for cash at the moment. Would you think this would be a worse case scenario or a pretty good chance?
 
this is what i tell all Dodge product owners ...ground the trans to the chassis and ground the ECM to the fire wall and the main ground from the battery.. all your sensors are 0-5 volt and the ECM takes and switches the sensor inputs to operate the high load devises through the relay/fuse box..battery corrosion or corrosion on any terminals will result in a circuit over load or sensor input malfunction ..remove the ECM connection at the ECM and clean terminals with contact cleaner ( battery disconnected) until shiny..then pak it full of dielectic grease.. this may solve it
 
I really hope not. Guess I should look into price for a rebuild. Any recommendations for a shop near Cumming? I hope it's something simple as I'm a little strapped for cash at the moment. Would you think this would be a worse case scenario or a pretty good chance?
this is a repair if the shop is not honest will end up costing you a trans rebuild for a 5 dollar part..get estimates and talk to many about it..
 
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