[Grandpa Jeeper]

I have finally fixed my mystery codes. P0300 (Multiple Cylinder Mis-fire) and P0306 (Cylinder #6 Misfire Detected)

This all started with a P0320 code (Crankshaft Position sensor). When coming to a stop the Jeep would randomly die. It would always start back up. This happened four or five times in the course of a week. I had a code of P0320 so I replaced the crank position sensor and all was good. Or so I thought.
A few days later while on the hi-way I saw the CEL flash three times. What the heck, no codes. A week later while on the hi-way the CEL flashes again. Again no codes. This goes on for a couple of months. I do notice that it when it flashes it is always as I am letting off the gas at the crest of a hill. The faster I am going the more often it will do it. Then one day I make a hi-way trip faster than I normally drive, averaged around 80mph and the CEL flashed at the crest of every hill but this time it locked in codes of P0300 and P0306. Misfire codes. I cleared the codes, checked Jeep forum for a fix but came up empty as to why I was getting the misfire codes. This goes on for a few more months and again it locks in with P0300 and P0306 codes. Not once in all the times this was occurring did I ever feel a misfire, the Jeep seemed to be running just fine.

In thinking this through, I didn’t have any trouble until after I replaced the crank position sensor. When I put in the new sensor it had a paper spacer on the end, the instructions said it must be left on as it would give the correct spacing for the sensor. I went back to the sensor, loosened the bolt and pushed it down as far as it would go. It only moved about a 1/32 of an inch but it did move. Problem solved, it is has been three months now, lots of hi-way miles no flashing CEL and no codes.

I am just posting this to possibly help someone else who has the same symptoms.

[GOLENJEEPTJ]

Yep, you always have to make sure of the new paper gasket on a new CKP for an automatic trans!

[Grandpa Jeeper]

Originally Posted by GOLENJEEPTJ

Yep, you always have to make sure of the new paper gasket on a new CKP for an automatic trans!

It was that paper gasket that caused my trouble. Once i set the sensor with out the paper gasket my troubles were gone.