My TJ hates me
- Thread starter Ccturley
- Start date
I recommend a new TJ.
Barring that, try using an OBDII reader to record all data from cold start to cutout.
Yep, snap on modus. This has been a diagnostic for the ages.
If i'm reading post #23 of this thread correctly. I think he's been there, done that, @Stump.
Yeah, I didn’t read far enough. I saw that.
OK... I need to source A replacement PCM C1(black) Plug. We opened the plastic and old plastic does what old plastic does and the Blue pin keeper broke.....................................................................................................................................................
A quick search found some on Ebay for 35.00 They were just advertised as TJ 96-2006 and.... they look old as sin.
A quick search found some on Ebay for 35.00 They were just advertised as TJ 96-2006 and.... they look old as sin.
Sourced some new connectors....
I think that I may have actually found the issue.
Pulled out the wire harness again on Saturday and ran it top to bottom. no broken wires. Re-loomed it and installed it. Connected up the old PCM to verify conditions agains the New PCM. Wouldn't even fire. No spark, No fuel delivery. Checked CKP solid pulse from sensor at PCM. Checked CPS solid pulse from sensor at PCM. Power and ground at PCM ASD jumped with testing relay for B+ continuous. Would not start. Reconnected to the new PCM, long crank but it started and was running for about 2 mins. We started testing, and I tried something that I haven't tried yet. I started really putting the squeeze on the black connector moving it around (wires etc) and bam it died. Shook thw wiring a bit and it started right back up really put the squeeze on it again and bam it died.
Took the connector apart and the Blue pin lock was cracked and loose. Now Im not sure wether or not I caused this by how hard I was manipulation the plug, but the fact I was able to kill it while doing so leads me to believe that It may have been broken for a while and time + vibration loosened it up enough to cause these gremlins. And of course now after messing with the plug i can pull out the pins from the back of the connector lol so... I will await my (hopefully) fix in the mail, install Test and report back wether I have set the Jeep on fire or spent the day cruising with the top off.
I think that I may have actually found the issue.
Pulled out the wire harness again on Saturday and ran it top to bottom. no broken wires. Re-loomed it and installed it. Connected up the old PCM to verify conditions agains the New PCM. Wouldn't even fire. No spark, No fuel delivery. Checked CKP solid pulse from sensor at PCM. Checked CPS solid pulse from sensor at PCM. Power and ground at PCM ASD jumped with testing relay for B+ continuous. Would not start. Reconnected to the new PCM, long crank but it started and was running for about 2 mins. We started testing, and I tried something that I haven't tried yet. I started really putting the squeeze on the black connector moving it around (wires etc) and bam it died. Shook thw wiring a bit and it started right back up really put the squeeze on it again and bam it died.
Took the connector apart and the Blue pin lock was cracked and loose. Now Im not sure wether or not I caused this by how hard I was manipulation the plug, but the fact I was able to kill it while doing so leads me to believe that It may have been broken for a while and time + vibration loosened it up enough to cause these gremlins. And of course now after messing with the plug i can pull out the pins from the back of the connector lol so... I will await my (hopefully) fix in the mail, install Test and report back wether I have set the Jeep on fire or spent the day cruising with the top off.
Damn, dude. You’re like Sherlock Holmes.
Personally, i’d love to see pics of the exact area/plug assembly you’re talking about. Hard for me to visualize, but i think it’s worth it for us TJ folks to have a mental picture of this failure in case one of us starts dealing with it?
Damn, dude. You’re like Sherlock Holmes.
Personally, i’d love to see pics of the exact area/plug assembly you’re talking about. Hard for me to visualize, but i think it’s worth it for us TJ folks to have a mental picture of this failure in case one of us starts dealing with it?
Attachments
Wrangler fix... the efforts they're putting forward, when they don't need too, to help me get this fixed is second to none. They've won a customer here.
Wrangler fix.... They've bent over backwards trying to assist me getting this figured out.... they've won a customer for life.
Edit:
Sorry for the double post
I used to work with a guy who....lets just say english wasn't his first language. One time my buddy Tim helped him out on something. He was so excited once he got it working that he brought it up in a status meeting with the boss. Dude says to the boss:
"Tim so helpful, he bend over forwards for me."
Boss goes "I didn't realize Tim was a bottom."
For an extra layer of fun, I should mention that the boss was openly gay, which made this be more than a little tense until the followup joke was made.
Are you de-pinning & transferring, or is the new plug pre-wired for you to splice in?
Jumping in here... as I'd love to know the final outcome as well. I've been all over the place with similar sensor issues, but for me it went straight to no start and hasn't started since.
Just sent out my PCM to WranglerFix and I've really been thinking about my wiring at the PCM as well. If there was a new harness available for sale I'd be buying it. But also thinking about just making my own to rule all this out. :/
Just sent out my PCM to WranglerFix and I've really been thinking about my wiring at the PCM as well. If there was a new harness available for sale I'd be buying it. But also thinking about just making my own to rule all this out. :/
Vtx531
TJ Addict
Hate to say it but I think the new harness IS available through Mopar - Approx $35,000. Comes with a new Wrangler attached. These things aren't made to last forever. :-/
I just read all the posts in this thread and would love to know the follow up too
What's crazy is if I still had my twin turbo 300ZX(91) I could still buy a new harness.
I guess the question is... who wants to help me source every connector so I can build my own? hahaha
I guess the question is... who wants to help me source every connector so I can build my own? hahaha
I took the new to me plug apart and took the unbroken blue keeper out and put it in my plug.
So just a quick update. We have a working theory on what he problem is. It's still not running but heres what I thin the problem is.
SKIM...
Now before we go down the rabbit hole I just want to say that my jeep does not have a grey chip key. I have the regular ole black key. My Jeep does not have a skim module.
SKIM...
I do not have a bulb in the cluster for the security warning.
What I haven't ever known about my jeep until this week is that on the early 2000 models they came with a security key installed in the PCM. and if your model has it then it does not have a module. Its the lock cylinder itself. when you put the key in it pushes out the tumblers and they make contact which parses the security key in the pcm and tell the ASD to allow the engine to run.
Now here's the suck part... the only way to know for sure if this is the case is with a drb scan tool that literally no one has anymore. My new PCM is supposed to have the skim disabled in it. but, its literally the only option left. I called in the big dog whose my buddy of nearly 25 years and he's a jeep factory tech. we've confirmed everything is working as intended, and that it should be running. So hes making calls to people to find the work around.
I learned something new this week about the jeep i've been driving for 24 years. Worse case scenario I send my pcm back to wrangler fix to see if the disabling of the skim some how got re-enabled through a hard reset.
So kids, the moral of the story is don't rule out SKIM as the culprit even when you don't have it... because you probably do have some form of it, and just don't know about it.
SKIM...
Now before we go down the rabbit hole I just want to say that my jeep does not have a grey chip key. I have the regular ole black key. My Jeep does not have a skim module.
SKIM...
I do not have a bulb in the cluster for the security warning.
What I haven't ever known about my jeep until this week is that on the early 2000 models they came with a security key installed in the PCM. and if your model has it then it does not have a module. Its the lock cylinder itself. when you put the key in it pushes out the tumblers and they make contact which parses the security key in the pcm and tell the ASD to allow the engine to run.
Now here's the suck part... the only way to know for sure if this is the case is with a drb scan tool that literally no one has anymore. My new PCM is supposed to have the skim disabled in it. but, its literally the only option left. I called in the big dog whose my buddy of nearly 25 years and he's a jeep factory tech. we've confirmed everything is working as intended, and that it should be running. So hes making calls to people to find the work around.
I learned something new this week about the jeep i've been driving for 24 years. Worse case scenario I send my pcm back to wrangler fix to see if the disabling of the skim some how got re-enabled through a hard reset.
So kids, the moral of the story is don't rule out SKIM as the culprit even when you don't have it... because you probably do have some form of it, and just don't know about it.
Final update!
Back on the road.
After running every diagnostic known to man kind and replacing the pcm,I had an unknown secondary concern. After installing the new pcm I was still having the same issue and after retracing diagnostic steps found a short to 5V ref between the ckp and cmp sensor circuits with the sensors unplugged and the wires isolated. I suspected an internal short in the re-manned pcm so i sent it back in for warranty repair. It came back and the short was no longer present. Now it would start and run for a few seconds and die. Pulled the new plugs back out and inspected, then replaced assuming fouling. same result. after another round of diagnostics, literally retracing my steps from beginning to end I decided for shits and giggles to take a sample of fuel from the rail. Pumped the rail dry into a container and poured it out on the floor and it wouldn't light... smelled like ancient barn gas. pumped the system dry and flushed with 2 gallons of fresh fuel, then topped off the tank with 5 gallons. son of a bitch started up and ran like a champ. 1300 miles later we're still problem free.
I'm not sure why the fuel spoiled, it was fresh when the issue started up as this is my daily driver. It did sit for nearly 4 months while I was running down the issue and I almost wonder if someone didn't mess with it while it was down for repairs. I'll never know about that part.
This diagnostic ran me through the ringer. So many symptoms, and events that didn't square with what the diagnostics were saying. I replaced parts that probably were good parts. In the end, it's fixed.
Couple of thoughts, if you're getting an intermittent p0340 know that it could be the CKP sensor and not the CMP sensor. In my case it was an internal fault in both the OE pcm AND the re-manned that was causing a short from the ckp to the cmp on the 5V reference. It wasn't the sensors or the wiring. the good part with that is I found issues that weren't quite a problem yet that allowed me to address before a failure. (loose pins in the plug due to a broken retainer and my #3 injector sleeve was split but not leaking)
Know what you know, but don't assume that what you know is correct. I never looked for an issue in the fuel system because I knew everything was good there... except the fuel itself. I never even considered that I might have an issue with the gasoline. Why would I, right?
At any rate I hope that this post helps others arrive at an answer for their issue.
Back on the road.
After running every diagnostic known to man kind and replacing the pcm,I had an unknown secondary concern. After installing the new pcm I was still having the same issue and after retracing diagnostic steps found a short to 5V ref between the ckp and cmp sensor circuits with the sensors unplugged and the wires isolated. I suspected an internal short in the re-manned pcm so i sent it back in for warranty repair. It came back and the short was no longer present. Now it would start and run for a few seconds and die. Pulled the new plugs back out and inspected, then replaced assuming fouling. same result. after another round of diagnostics, literally retracing my steps from beginning to end I decided for shits and giggles to take a sample of fuel from the rail. Pumped the rail dry into a container and poured it out on the floor and it wouldn't light... smelled like ancient barn gas. pumped the system dry and flushed with 2 gallons of fresh fuel, then topped off the tank with 5 gallons. son of a bitch started up and ran like a champ. 1300 miles later we're still problem free.
I'm not sure why the fuel spoiled, it was fresh when the issue started up as this is my daily driver. It did sit for nearly 4 months while I was running down the issue and I almost wonder if someone didn't mess with it while it was down for repairs. I'll never know about that part.
This diagnostic ran me through the ringer. So many symptoms, and events that didn't square with what the diagnostics were saying. I replaced parts that probably were good parts. In the end, it's fixed.
Couple of thoughts, if you're getting an intermittent p0340 know that it could be the CKP sensor and not the CMP sensor. In my case it was an internal fault in both the OE pcm AND the re-manned that was causing a short from the ckp to the cmp on the 5V reference. It wasn't the sensors or the wiring. the good part with that is I found issues that weren't quite a problem yet that allowed me to address before a failure. (loose pins in the plug due to a broken retainer and my #3 injector sleeve was split but not leaking)
Know what you know, but don't assume that what you know is correct. I never looked for an issue in the fuel system because I knew everything was good there... except the fuel itself. I never even considered that I might have an issue with the gasoline. Why would I, right?
At any rate I hope that this post helps others arrive at an answer for their issue.
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