Driveability Issues

TenaciousJ

New Member
Original poster
Joined
Jul 1, 2016
Messages
7
Hi All,

New member, first post, could use some help. Have a 2001 TJ with a 4,0L manual and have been experiencing issues similar to a bad crank position sensor. Mainly stalling and intermittent loss of gauges (I could tell when it was going to act up as the gauges/odo wouldn't work). Changed out the crank sensor with a new OEM but no luck. Right after that, started getting check engine light and the P1391 code, intermittent cam/crank signal.

After much reading, decided to check and make sure the cam position sensor was aligned correctly with the engine at TDC as outlined in the FSM. It was a bit off, but when I adjusted it and started the engine, the P1391 was pending again, and P0352 was set with 0351 and 0353 to follow, Coil A, B, C primary/secondary. I'm pretty sure these are a result of incorrect CKP timing.

I did notice a little rotational play in the OPDA shaft, if I had to guess I'd say more than 1/16 but less than 1/8. Wondering if that's normal or could be an issue? Not quite sure where to go from here and could use some input. Thanks.
 
Sure, if you take a look at the image below, you can see part #3 Pulse Ring, that part is attached to the Oil Pump Driveshaft #5 and rotates when the engine is running via the Driveshaft to Camshaft Gear #4 to interrupt the field in the CMP #1 which sends the CMP signal to the PCM. So when I grab the pulse ring and check for rotational play, it rotates a little bit as described above. I'm wondering how much play is acceptable and if it may be the cause of the problem, or at least why I can't seem to adjust it proplerly? The OPDA housing is clamped securely and doesn't rotate.

CMP Assembly.webp
 
I'm not in front of my computer so I can't check at the moment. But do you happen to have a service manual? My guess is it should list the amount of acceptable play in the pulse ring.
 
I do and it describes the process for setting the CMP but doesn't say anything about play, unless I missed it. Also doesn't give any testing procedure, which was a bit surprising.

The other thing that was a bit odd is that on my engine there wasn't a timing mark scale like in the diagram below, just a single pointer as seen in the pic. I'm assuming the pointer is for TDC as I don't think the timing is adjustable?

4,0 Timing Marks.webp
4.0 Timing Pointer.webp
 
Thanks for checking that, appreciate it. I think the 05-06 have a different style OPDA than the 01 that I have and seem to be very problematic based on the number of threads on them. It's been difficult to find out if the 01 OPDA assy should have any play or not as all searches seem to give 05-06 results.
 
I was curious what a new camshaft synchronizer would cost from Mopar, but all the parts websites show a distributor instead of the synchro assy (BTW, is it incorrect to refer to these as an OPDA on a 2001?).

Found this one below on Amazon from Borg Warner, there are also others from Dorman that are cheaper than this. But short of a Mopar unit, BW seems to have a good rep if I decide to change it out?

https://www.amazon.com/dp/B000BZBATE/?tag=wranglerorg-20
 
After more searching I think the link above is just for the cam sensor even though it shows the whole synchronizer unit. I found this BWD unit below I might try. Also came across another thread or two where symptoms were the same as mine and the CMP output even looked good on the scan tool, but changing the complete synchronizer assembly finally solved the problem due to play in the pulse ring. Just can't seem to nail down how much play is acceptable. But from the descriptions, it seems like the play is all but eliminated when the new assembly is installed. What a tricky problem to track down!

http://shop.advanceautoparts.com/p/...leIdSearch=49693&searchTerm=cza109&showTitle=
 
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Does anyone with this style cam synchronizer know or remember how much rotational play the pulse ring has when it's installed in the engine?