Hey guys,

Been doing some searching and found very similar question with no answers, so here we go again. if you got a renix help a brother out.

running over my sensors trying to figure out why my 88 xj is running super rich (black soot, almost choking out) found that some one has done some splicing on the knock sensor wiring.

starting at harness by fire wall, there is yellow/black, purple/white, and then black. the black turns into an unshielded braided wire and runs with the yel/blk, prp/wht down to the sensor and then just terminates. it is all wrapped in foil.

Can any one tell me what up with this. does if have to do with interference shielding? Cant tell from the wiring schematics.

 

The knock sensor has a plug on it like a fuel injector and is screwed into a boss on the driver's side of the block just above the oil pan level.

The knock sensor will not ever cause any driveability problem. All it does when hooked up is send a signal to the ECU if it detects pinging so the ECU can momentrily retard the ignition timing.

Your sooty black rich-running issue is generally caused by problems with the MAP sensor and/or the vacuum tubes running to it. Be sure the vac line to that sensor is not cracked, melted, plugged, and it's plugged into the throttle body securely.

 

Cool thanks for the info.

still dosnt tell me exectly what that braided wire does but at least i don't have to worry about it causing my issue.

 

Deor- I know this is an old post. Just wanted to add to it for anyone coming by later. from what I've read, I believe the shielding on the wire to the knock sensor is because the knock sensor is basically a vibration/frequency detecting microphone and the shielded wire helps its to not pick up extraneous input.

 

.