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  Topic Review (Newest First)
09-26-2019 03:52 PM
john5547 Im definatly only getting 3V to the cmp connector. Whats the correct procedure for replacing only the connector without just cutting it off? While cranking im only getting 2.5V
09-26-2019 02:44 PM
john5547 These are the chafed wires. Green/black, orange/black, white/black, and an off red or pink/black
09-26-2019 02:33 PM
john5547 Back to checking the wiring. Bought a kit to replace the connector to cmp. In the process im dragging out the harness and inspect and to get a better look at the wires that were chafed.
09-25-2019 04:02 PM
john5547 Alot more frequent stalling/missing/stuttering
09-25-2019 03:26 PM
john5547 After putting in the mopar camshaft position sensor the vehicle now runs WORSE. I dont understand this unless it needs a relearn or something....
09-22-2019 07:28 PM
99wjtx Yes. Sorry - I guess I overlooked that if you had already mentioned it. In that case I really have no idea.
09-22-2019 06:47 PM
john5547 Ive already replaced the PCM also, that is the same thing as the ECM right?
09-22-2019 06:40 PM
99wjtx Then all things considered it is sounding to me like the ECM. Still, replacing the crank sensor does make sense first, just in case. Maybe one of the pro Jeep guys who hasn't commented yet will step in here with some advice or experience.
09-22-2019 06:33 PM
john5547 Im sorry i got the sensors confused. I already have replaced the CPS with a genuine mopar sensor. (no success) Waiting on the MOPAR CMP sensor.
09-22-2019 06:25 PM
99wjtx I had an intermittent problem with an occasional stall just last year. I was so resisting the idea of replacing the CPS due to how inaccessible it is (I HATE dropping the WJ starter!) that I just skipped right to replacing the ECM first. Since I wasn't getting any codes I figured well, the ECM is probably flaky. Well, after replacing the ECM for a while I had no more stalls and then one day it stalled again. At that point I bit the bullet and ordered a CPS. I went ahead and got a genuine Mopar hoping to reduce the chance of having to do it again anytime soon. As it turned out, replacing the CPS fixed the stall problem which never recurred again.

This all happened about a year after I rebuilt the engine. I replaced a lot of components that might not have been strictly necessary to replace when I rebuilt it - injectors, etc., but at that time I chose to risk not replacing some sensors and the CPS was one of them. The engine had overheated and essentially melted down. That's the state it was in when I bought it for rebuilding. Looking back now I suspect the intense heat may have damaged the CPS but I wasn't thinking about that during the rebuild.

Skipping ahead and replacing the ECM instead of the more logical choice of the CPS first also had something to do with wanting to more completely finish my "restoration" project. A new (not really new but serviced ECM) while I could still actually find one for a decent price seemed like a way to do that.

But the moral is, the most likely explanation is usually the right one.
09-22-2019 06:12 PM
john5547 Thanks so much 99wj. I did already replace the pcm with no success. My genuine mopar CPS is on its way. After that arrives and i see what happens with that, i may look more into the timing. As i said in the beginning the engine was rebuilt 63k miles ago ***From the previous owner*** And id like to think they replaced the timing chain and tensioners in the process. But im running out of options so i may look into the timing if the cps doesnt change anything.
09-22-2019 06:03 PM
99wjtx After reading through this thread, in my amateur opinion it sounds like there's still a problem at the crankshaft position sensor (more on that below). Otherwise, it could be a mechanical issue with the timing or the ECM itself. If the ECM has become flaky, of course they really aren't serviceable but they are easily replaced if you can find a good one.

If it's a mechanical problem, there could be one or more broken or severely worn timing chain tensioners. If a chain has skipped a single link, it may still run but not very well. Regardless, that would confuse the computer because the crank sensor and the cam sensor will be reporting irreconcilable data which would likely cause the ECM to throw a code.

As for the clearance of the CPS to the tone ring, as I understand it, it uses an electrical "hall effect" for the pick-up and so positioning to a micro criticality is probably not necessary. It shouldn't touch the tone ring but otherwise it should be able to operate within a range of tolerance either nearer or farther. It seems odd that it ever touched at all which makes me wonder if you didn't somehow get a similar but not quite correct CPS or the CPS was manufactured poorly. You should never need a shim with the WJ CPS and I've never heard of anyone needing one. The only problem people sometimes run into is that the bolt will bottom out before snugging up the CPS to the mounting point on the block due a design revision Mopar made at some point. You can fix that problem with a simple washer.

In any case, I'd bite the bullet and try a genuine Mopar CPS first before I tore into the mechanical aspects of the timing or replaced the ECM.
09-22-2019 05:38 PM
john5547 What prompted me to check is the connector will not “snap” into place when connected. It just slides off and on.
09-22-2019 05:35 PM
john5547 Getting desperate on things to check. This is the cmp wiring cnnector. It is good correct?
09-21-2019 12:17 PM
john5547 After installing a mopar ckp its running alot smoother. Although im still getting the code for signal loss to ckp/cmp. I did install a washer under the mounting bracket to act as a spacer due to the one i took out being scratched. Would you take the washer out and try again? Id hate to screw up another $90 sensor.
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