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-   -   01 Died and Won't Start (Sort Of) (http://www.jeepforum.com/forum/f11/01-died-wont-start-sort-1543324/)

ratjaw 06-30-2013 07:16 PM

01 Died and Won't Start (Sort Of)
 
Well this has me stumped.
01 XJ died the other night. We were doing 45ish and it died. Dead. Crank but no start. Had it towed home. Will only crank but won't start. Put a gauge on the fuel rail and had the required 42 ish psi. Researched JF and figured it was the CPS as is normal for a Jeep. Got the multimeter and checked... open circuit between any combination of the three CPS pins. Have 5V at the outside pins on the chassis side of the CPS connector. Swapped the relays around with no change. Figured I would replace the CPS tomorrow. For grins I had my wife crank the engine while I had the intake hose disconnected from the air cleaner and gave it a squirt of ether. Then things got weird...


On occasion, the engine would "backfire", meaning it would spit compression out of the intake hose, like the timing was off. Then, it just started and ran fine. Shut it off and tried to restart it and nothing. Put my hand over the intake hose while my wife cranked it and felt an intermittent "suck". Then, when she quit cranking, the engine started, but was only hitting on a few cylinders and was slow to rev. Shut it off and recranked... Started and ran like new. Shut it off and when it did start, it had an ignition knock, like the ignition timing was way off. Shut it off again and restarted and it would crank but not start. Key off, then crank again and it ran fine, revved up properly with no hint of trouble.


What is this thing doing?



It appears that my Jeep is playing Russian Roulette with the ignition switch. Every time I crank it, it decides to give me a different symptom. I think I liked it better when it just wouldn't start.


Any ideas?

dave564 06-30-2013 09:27 PM

How many miles?? Did you check to see if it saved a code?? Need more info..

Just based on your post it sounds like the cam, distributor sensor, or a combo of the 2 are jumping time. I think a chain is in your future...

ratjaw 07-01-2013 06:11 AM

Just short of 200,000 miles. Being an 01, there is no distributor. I agree, it sounds like cam or cam timing, but if it were a base engine timing problem, there should be an associated noise, like valves smacking pistons or something like that. Because it runs well, then poorly, then well, I have been thinking ignition timing. I think I'm going to pull the cam sensor and have a look.

I have no code reader to check for codes.

dave564 07-01-2013 11:15 AM

Cam sensor is what I meant, just couldn't think of what it was called. I think it is jumping a tooth one way or the other at the chain, specially with the miles on it.

The symptoms you described scream timing chain to me. I don't think that the 4.0 is an interference engine, so if it did jump time it wouldn't eat the valves, but it would run like crap if at all. Then of course when you start or stop it, it jumps back to where it is supposed to be and all is well again.

ratjaw 07-03-2013 05:33 PM

I pulled the cam sensor and found that the magnet for the pick up had broken off and was stuck to the inside of the rotor. When I inspected the rotor, it felt loose. I then pulled the cam synchronizer (after I rotated the engine to #1 TDC compression) and found the bushings were worn. A quick trip to Napa and I have a new synchronizer assembly with cam sensor. Installed and the engine fired right up. Tomorrow I need to fine tune the adjustment and everything should be back to normal.

dave564 07-03-2013 08:28 PM

Good to hear that it was a simple fix for ya.

Kevin108 07-04-2013 07:41 AM

Quote:

Originally Posted by ratjaw (Post 15637986)
I pulled the cam sensor and found that the magnet for the pick up had broken off and was stuck to the inside of the rotor. When I inspected the rotor, it felt loose. I then pulled the cam synchronizer (after I rotated the engine to #1 TDC compression) and found the bushings were worn. A quick trip to Napa and I have a new synchronizer assembly with cam sensor. Installed and the engine fired right up. Tomorrow I need to fine tune the adjustment and everything should be back to normal.

http://www.jeepforum.com/forum/f11/h...ensor-1145301/


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