Just curious, but where did you get the CPS? As a professional mechanic with over 20 years experience, I've learned the hard way to never use anything but O.E. Jeep/Mopar crank sensors on these engines. I've traced too many drivability issues back to a NAPA sensor.

 

The parts are all mopar. The t.p.s is reading fine. I checked it with a scanner and with a dvom at the connector and they read the same. the only thing that isn't making sense is when the timing advances to 113deg. the computer isn't seeing that. the timing light that we used also reads rpms and when it starts missing the tach on the gun reads 5500rpms. the computer is not seeing that either. I am going to drop the converter just to see if that changes anything, even though the back pressure is only 1.5lbs.

 

Do you have access to a known good computer to swap out and see if that is the problem it seems your running out of options here. We have a jeep bone yard close the owner let me borrow a computer when I was troubleshooting mine and had the exact problem. Even a used one from the bone yard. You did reset the computer when you changed the sensor/s by shorting the pos battery cable to the neg for at least 30 seconds. Then you turn the key on but dont start it and turn the lights on then off and turn the key off.

 

is it possible your flex plate or flywheel is cracked around the bolts? ive seen it before where it will idle ok, but once tourque is apllied to the broken flex plate it twists enough to make your timing wonky and the crank sensor read funny. ide pull the trans and check. you have relaced the sensor too many times for it to be a bumb sensor. next look mechanical.

 

I did reset the computer. I used a computer out of a customers car. same problem. I had one of my mechanics remove the inspection plate and checke the flywheel for run out. he said it was fine.

 

Just throwing stuff out there could the coil be bad internally and run it in the dark and see if you see any sparking under the hood. As thorough you have been I`m guessing you took all the grounds apart and sanded them metal to metal especially the three on the engine with the bolt that holds the dipstick tube in.

 

All the grounds have been checked, even ran a new ground straight to the battery and its had two coils on it both do the same thing. I promise i am not making this up. I work at a shop in nashville and this has got 5 ase certified technician scracthing their heads.

 

When I was in the army I ran across a Tank that had wiring issues in the turret we took a harness apart to see why it had a short in it and someone stuck a needle through the middle of the loop. The jeep has one hella big loop in it I couldnt imagine trying to test every wire for shorts and continuity. I did it in my 83 ford ranger and that was a three day project. Do you have a good wiring manual because it is quite extensive. It took me over a day to figure out my cruise control and had to replace the clock spring. You can get the complete wiring book here for free I will try and find the guy that turned me on to it if need be.

 

I have checked the wiring. I am 90% sure it is a mechanical issue. We are going to recheck the flywheel just to make sure its not cracked.

 

I hope you figure it out soon be sure to post the solution

 

Checked the flywheel and its fine. We are going to run new wires from the crank sensor to the computer and see what that does.

 

I had a first yesterday I was pulling into the bone yard to get a wheel flare for my XJ and the electric fan started ratteling as I was pulling in the driveway. Three minutes later it was fixed for $10 plus $5 for the flare. I fixed the owners furnace last year and get the employee discount now. I hope that fixes your problem I couldnt even imagine having to swap out the harness way too many wires.