• Welcome to the new NAXJA Forum! If your password does not work, please use "Forgot your password?" link on the log-in page. Please feel free to reach out to [email protected] if we can provide any assistance.

Xj broke down while traveling

maxbraketorque said:
This is interesting to see and want to make sure I understand what caused the cam position sensor tone ring to stop rotating. Had the lifted off the motor and was no longer engaging with the camshaft (and no longer pumping oil)? Or can the gear on the oil pump driveshaft come loose?
Click to expand...

No to all the above, if you sucked something that big (no oil pump sreen) into the oil pump it would just shear the shaft or the distributor gear and vertical movement is not possible.
 
I honestly can't remember if it rotated when I pulled it off (still engaged with cam teeth or not). The synchronizer gears were worn unevenly with one section almost completely sheered off. I'm guessing it stopped being engaged with the cam in that area... Not sure what caused the uneven wear though. The oil pump and screen are new (~4k miles)
Previous owner neglected the jeep and was pretty sloppy with his work so I'm sure oil changes weren't routine. I've also got a mild lifter tick. He had a shop put install a performance head when the OEM one cracked. Didn't say anything about a cam swap so I'm guessing the cam is stock (alignment wise). I'm at 200k miles
 
Does anyone know how to resync fuel timing without the DRB scan tool?
I think the oil pump slot got misaligned when things got bound up or when I installed the new synchronizer . I was unable to drop in the replacement synchronizer without slightly rotating the oil pump slot maybe 30 degrees, which caused the fuel timing to be thrown off. ��
 
Oil pump position is irrelavant, you need to set the distributor when the engine is on compression tdc.
 
Ya that's what I did. Set it to tdc compression and aligned the holes. Runs like crap, hesitating, rough idle, backfiring through intake with load... I rotated the shaft couple degrees clockwise and it doesn't start. Went counterclockwise from baseline and the same symptoms. Can't get it to run right at all. Spark plugs are fouled black
 
I'm wondering if my timing marks on the crankshaft pulley are off or misaligned? I verified with the screw driver down the spark plug hole but there's such a huge range on the numbers where I can't feel the piston move any more. I can feel it start going back down about a quarter/half inch past the degree plate
 
Vitzaa said:
I'm wondering if my timing marks on the crankshaft pulley are off or misaligned? I verified with the screw driver down the spark plug hole but there's such a huge range on the numbers where I can't feel the piston move any more. I can feel it start going back down about a quarter/half inch past the degree plate
Click to expand...

I was wondering how you were going to do the alignment. From what I saw, the late model XJs have a tiny slot on the harmonic damper and then a single line on the block. Is that what you have on your XJ?

Did you disconnect the battery after your initial alignment?

The videos I watched seem to suggest that there is a pretty wide range of camshaft position sensor body angles where the ECU can successfully sync the camshaft position sensor signal.

Is there a chance that your camshaft position sensor is damaged, or maybe there is something off with your crankshaft position sensor replacement?
 
maxbraketorque said:
I was wondering how you were going to do the alignment. From what I saw, the late model XJs have a tiny slot on the harmonic damper and then a single line on the block. Is that what you have on your XJ?Did you disconnect the battery after your initial alignment?
The videos I watched seem to suggest that there is a pretty wide range of camshaft position sensor body angles where the ECU can successfully sync the camshaft position sensor signal.
Is there a chance that your camshaft position sensor is damaged, or maybe there is something off with your crankshaft position sensor replacement?
Click to expand...

There's at least 2 reasons for that:
1 - the sensor has a tolerance range of at least + or - 3* with no affect on anything
2 - the assembled body can be rotated to any position as long as the pick-up was timed correctly
 
It's just so weird this isn't working.

I do have a tiny slot on the harmonic balancer but the plate with degrees have increments of 8° 6° 4° 2° 0. With notches in between the numbers. I'm guessing the timing chain cover was replaced at one point. The timing chain and sprockets were replaced by a shop before we started our road trip journey and have 4k miles on them...

The synchronizer came with a cam position sensor. I also replaced the sensor today with a new spare one I had. Both sensors exhibited the same symptoms. The sensor is pointing towards the firewall and is parallel with the engine. With the engine in TDC, the open cup inside the synchronizer faces the firewall and is slightly angled towards driver side.

I did disconnect ground on the battery after the synchronizer install.

I'll shoot a video of it tomorrow

My camshaft sensor connector (wiring harness side) does have some exposed/l wiring on the base and the plastic insulation is brittle. I ordered a replacement connector and going to pick it up tomorrow so that I can solder it in.

I'm just totally stumped. I've got the factory service manual and have followed the steps to a t. I'm guessing something is fudged with the degree marks on the timing chain cover? Spoke to a buddy today and said all the timing chain covers from '84-'01 are identical so the numbers should correspond...

I'm totally stumped and have no idea what's happening here
 
Vitzaa said:
I do have a tiny slot on the harmonic balancer but the plate with degrees have increments of 8° 6° 4° 2° 0. With notches in between the numbers.
I'm guessing something is fudged with the degree marks on the timing chain cover? Spoke to a buddy today and said all the timing chain covers from '84-'01 are identical so the numbers should correspond...
Click to expand...

The 2000-01 has factory marks! The harmonic balancer spinning is a real possibility though.
 
RCP Phx said:
The 2000-01 has factory marks! The harmonic balancer spinning is a real possibility though.
Click to expand...

I'm not following the timing marks comment. Are you saying the '00/'01 timing marks on the timing chain cover would have the 0 at a different spot than pre '00?

Have you or anyone ever heard of the harmonic balancer mark getting displaced? Ive never fumbled with one so I'm not sure how it's assembled (pressed vs welded)
 
The potential problem with the balancer is that the outer ring will move relative to the center. The two are held in relative position by a ring of rubber in the center. Over time the rubber degrades and the outer ring could slip.

By this time, most XJs probably need to have their balancer replaced. Note that this is not something you want to hammer into place. Balancer removal tools and installation tools may be "rented" from some parts stores.
 
Vitzaa said:
I'm not following the timing marks comment. Are you saying the '00/'01 timing marks on the timing chain cover would have the 0 at a different spot than pre '00?

Have you or anyone ever heard of the harmonic balancer mark getting displaced? Ive never fumbled with one so I'm not sure how it's assembled (pressed vs welded)
Click to expand...

Yes, I've had one fail or slip on me. I replace them if I buy a used XJ.
 
You must log in or register to reply here.

Similar threads

W
1999 XJ - No start - PCM?
Replies
1
Views
2K
Tim_MN
Tim_MN
Anak
Well Crud! Another '96 XJ with an Intermittent Stalling Issue
2
Replies
29
Views
5K
XJJeeper59
XJJeeper59
A
Long crank when engine warm
Replies
15
Views
3K
aquaman788
A
T
1999 XJ crank, no start after engine swap
Replies
0
Views
300
Turbo_Ted
T
D
Feeler: 1999 XJ Sport
Replies
2
Views
315
dart70LA
D
Back
Top