Red River T

After driving my recently acquired '97 GC w/ 4.0 for several months, last week it began stumbling occasionally, sometimes running rough enough that the engine shook pretty bad, then it began dying randomly. It would start right back up, but a couple of times it died while at speed and would backfire (loud bang out the pipe like it fired with a valve open and a couple of times spit back through the intake).

I had run it nearly dry due to absent-mindedness and had to buy gas at a place I don't trust. The 2nd time I started it after buying that gas, the stumbling crap started. Of course I thought bad gas. Then it got to doing the worse stuff. It threw engine codes: misfires, manifold pressure high, bad coil. Took off the MSD coil I had put on during the tune-up steps I had taken after getting the Jeep and put the original back on. It started and ran fine for 10 minutes. Drove 11 miles to work with no issues. When I was leaving for home, it started the stumbling, bucking, spitting, dying stuff again. The 4th or 5th time I restarted it, it then ran fine back home, except I think I felt it die once at 65 mph before picking back up.

I was checking out what it was going to take to change the Crank Position Sensor and I saw that the wiring connection for the CPS was soaked in oil from a valve cover leak. I tried cleaning it with brake cleaner. After that it wouldn't start at all, so obviously I had made it worse. I took the wiring harness portion of the connector out of the plastic protective sleeve so I could pull it closer and I noticed that there was ~1/2" of exposed wires between the ends of the insulation and the connector body and it was twisted half around so the wires were touching. I put heat shrink wrap and then electrical tape around each wire, it started right up and has run fine ever since. It actually runs better than it ever has. It had a fairly frequent variation in the idle which is now gone. (I haven't gotten around to removing the throttle body and cleaning the idle control.)

I haven't it driven much, maybe 80 miles or so until today. Today I got a CEL after driving in city traffic ~10 min, the first time I've driven it in town since the problem. The code is 12, which one interweb search said is cam timing retarded.

Anyway, I read threads on here and saw several people say they had changed their Crank Sensor and it seemed to have fixed their random dying problem, but only briefly. I thought I would share my experience with the wiring connector.