Hello everyone

Could someone please post the procedure to change out the 2 crank position sensors? Any help would be greatly appreciated

Thank you,

Evan
1989 Xjs convertible

 

The sensors are clearly visible under the car. One on the engine front cover below the crank and one at the rear at the flywheel. Two bolts for each. No problem as far as all that goes.

The tough part is reaching the harness connections (topside) and threading the harnesses in/out of their intended path. Don't pull the old ones out without carefull noting the path and/or using a piece of wire to pull the old wires out while plling the new wires in, if you get what I mean.

Cheers
DD

 

I know exactly what you mean. Thank you. Tackling it tomorrow.

Evan

 

To bring this thread back to life for the simple question,,, are the two sensors crank position sensors exactly the same part? I have a no start situation with my 1990 XJS convertible that started yesterday... I recently changed the front with no problems.

lately I've been and had been doing a LOT of digging around and pushing and pulling wires around to get to and (unsuccessfully) remove the expansion valve for the a.c. system. Removed balance pipe and fuel rail,,, but moved wiring around back there as much as needed - lots really - noticing the crank sensor plug and wiring. Put everything back and NOOO spark. No start. Suspecting the rear sensor, for some reason...

Are the front and back the same and,,,, open to any suggestion for the no start/spark situation...

 

The first thing I would check with a no spark situation on a Marelli is the white wire, this goes from the Marelli ECU to the engine bay near where the Lucas ignition module would have been there is a connector there, then it heads off the the FI ECU in the boot.

Check the connector.

 

Good morning warrjon, thank You!

So I went back to it and pulled the balance pipe out and started inspecting the wires expecting to have to start cutting open taped looms of wire. I noticed (I'd known this thing needed attention) the connector in the photo with a charred end and crispy wires from a "small" fire that happened with PO... I know it sounds bad and is, but I had been ignoring this for some time. Out of sight out of mind so to speak and a bunch of other things needing doing and,,, not actually driving her so much anyways - for now...

anyways, I removed the connector spliced the wires appropriately and she fired right up...

Q: why such a big connector??? Is there something about the plug in the pic,,, just at the back and under fuel rail, throttle stand etc,,, that I should know about?

 

I can not see a pic but if it's the tach wire cheapo Jaguar used the same harness and the connector used to connect to the Lucas ignition amp, Jaguar just plugged the Marelli into the wire and away they went.