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I'm having a weird CPS issue that I'm hoping something else has run into before. A couple months ago the original CPS wiring became so brittle that it broke off at the sensor. I thought "No big deal, I'll just replace it." Put a new sensor on and initially everything worked perfectly. A couple days later I go to use the truck and nothing, spin no start. REMII reading 0 rpm while cranking. Tested resistance and while it seemed good I figured maybe I just had a poor quality new sensor. Looked online and found a different brand high altitude CPS. When it showed up, after replacing the battery (someone may have left the lights on, one of life's little mystery's) installed the new sensor and again runs great. Take it for a drive and it runs like a scalded dog. A couple days later, spin no start again. REMII reading 0 rpm while cranking. Good voltage at battery, no voltage drop along cables, good grounds. Checked that I didn't have pins pushed back or spread in connector. Tested AC voltage coming from sensor, right where it should be. Tested voltage on harness side, and after that it miraculously cranks right up and runs without any issues. Next day spin no start until I test voltage and then it fires up. I'm perplexed to say the least. I was thinking maybe an issue in the ecu so I have one coming but I'm all ears if someone has any other ideas

What is the best CPS out there for an 89 4.0L. Rain ,sleet, snow out and mine must be getting weak, left a wake this afternoon for a good friend and MJ wouldn't start, unplugged and plugged fired right up so I will be replacing soon, is MOPAR still available?

1988 Jeep Comanche 4.0 AW4: My truck died abruptly in the middle of traffic yesterday morning and then would not fire no matter how much I cranked it over. After work, I went to Autobone and bought a new crankshaft position sensor (Per my research it appears as though I should have went to the dealership instead and bought an OEM sensor which is what I may end up doing.) After installing the new sensor my truck fired up instantly. I took it once around the block and then figured all was well. Today, I drove my truck to work and it started miss-firing, jerking, sputtering and wanting to die when idling. I had to keep my foot on the gas so it wouldn't conk out. I have a Renix Engine Management unit plugged in and I noticed the ignition timing was sporadic, jumping from 14 to 20 degrees and every number in between when idling at red lights. Does this sound like a bad sensor out of the box? Did I get boned by Autobone?

86 2.5 L I don't know what to think I have changed the coil, the distributor cap and rotor, the map , I tested the cps it read like 217 ohms. should I replace that to?

Hello everyone. I'm new to the forum. I just picked up my first Comanche yesterday. Snagged a non-running 86 4x4 auto model for $500. I wanted to start this thread so I had a place to post progress on the truck, as well as get feedback and tips. Plans for the truck so far are to get it running, repair any rust, paint, bedliner, wheels and tires, and then use it as a daily driver to keep the miles down on my TJ. Eventually I would like to do a lift, bigger tires, and a motor swap. The truck will mostly be used to drive back and forth to work, hauling loads of mulch, and the occasional light trail riding. I will post pictures as soon as I figure out how. Thanks everyone.

So, I'm building an 87 Comanche. I'm using a 91 HO Cherokee for the engine, transmission, T-case, electrical, dash and so on. Started a awhile back. So, I bought a new CPS sensor. Started installing it. And I'll tell you what, I have quite a few choice words for the guy that decided that location was a good place. I hope he suffers an eternity of having to replace these. On a clean truck, not bad, but on a well driven one... I spent hours trying to get it installed. The dang bolts won't thread in the holes, with sensor. But, sure as hell, I can hand thread with out the sensor. put the sensor back, and put the bolts in, turn for F-N hours, and never grab a thread. Well finally get dat b!tch up, and start to connect it. I can't find the matching connector on the harness! W.T.F!!! I've read there may have been a service bulletin to relocate connector to inside the cab. Take dash apart, and I can't locate a matching connector. I have 3 other XJ / MJ's to compare. 2000 XJ, CPS looks like it connects to harness with the transmission on passenger side. My 91/87 MJ no have that... 1990 MJ, CPS is connected to a GM style connector off the injector harness. My 91/87 MJ no have that same style plug.. Now, there is an un used round 3 pin connector on the injector harness. I always figured it was for a different TB. So, I goto Autozone, and have them show me a CPS from a 91... Damn it!, looks like it uses a round connector. So, I just spent some time in CPS HELL, and installed the wrong damn sensor... Now, I got to remove that sensor, buy correct one, and pray I can install in less then 8hr... before all this started, I went to a u pull it salvage yard, and pulled a CPS. It only took me 10min to remove it. I wanted to bolts, cause I did not know the size needed, I figured if I was going through the pain of installing a CPS, I may as well start with correct bolts. The F N issue is I could not get the bolts to bite as I turned the wrench. I used paper to make sure the bolt was not sliding down into the socket... Anyway, for thats don't know, there are different plugs on the CPS used. now I know. I'm debating on just cutting both ends off and putting on GM style weather pack connectors.