Hi,

I am helping my brother with his recently purchased 1998 XJR w/65k - I've been reading this board quite a bit since then out of curiousity

Recently the car is in "reduced power" mode and has several codes (and of course engine power is way down. Additionally he said the car has stalled out on the highway several times and sometimes the car takes excessive cranking to start.

Here are the codes:
P1336 Crank/Cam Sensor Range/Performance
P1000 readiness monitor not set
P1637 Can Link ECM/ABSCM Circuit/Network Malfunction
P1720 Vehicle Speed (Meter) Circuit Malfunction
P1797 Neutral Switch Circuit Malfunction

I advised him to stop driving it until he figures out the problem since it could be the chain tensioner issue, being that there's a P1336. Is that a typical code to be seen when the tensioners are going?

I wasn't thinking Nikasil the car was not down on power before the codes, and there's not oil on the filter, etc.. although if it were running ok I'd do a compression test.

So am I on the right track attempting to check/replace the tensioners?

thanks!

-Dan

 

ECM AJ26
P1336 CKPS / CMPS sensors synchronization malfunction.

P1637 CAN ABS/TCCM token missing

TCM W5A580
P1720 ABS rear wheel speed CAN messages corrupted or ABS token message corrupted

P1797 CAN ECM messages (all) corrupted or CAN ECM token message missing

I think you might have a CAN bus fault?????

The P1336 is a synchronization fault. If all the connectors and sensors are OK then look for mechanical faults.

I witnessed this fault when a guy a few stalls down from me at the Jaguar Dealer used the crank lock tool to hold the crank for front damper removal.
LOOOOOONG story short, he bent a segment in the torque converter drive plate and the sensor lost count repeatedly!!!!!!!!

For 2 days he replaced components until a few of us suggested he might have bent a segment for the CKPS. He SWORE he did not use the tool to lock the crank for damper removal but after the gearbox was out, WE SAW the bent segment!!!!!

New torque converter drive plate and all was normal.
You could also have the 'B'bank intake cam reluctor damaged or missing???
It might have fallen off or the 'tooth' broke????
Did the left ('B'bank) cam 'jump time?????

I think you have 2 problems.
ABS/CAN bus faults
P1336 CKPS / CMPS sensors synchronization malfunction

Time for diagnostics!!!

bob gauff

 

Thanks for the info - I wish your shop was near Philly, PA

I'll post back when the problem is fixed for future reference

 

Depending on the scan tool, I believe that many CAN bus codes are artifacts of connecting the scanner. At least with the pro scan ELM system, I know they are. I would worry about the CAN bus after the other codes are cleared.