I had this code thrown at me this morning with the reduced performance warning and orange light.

OBD says its the Knock Sensor Low Circuit (bank 1) that is at fault. I expect its an easy job to rectify if the sensors are both located on the left and right centre of the engine.

I have read the thread on changing the Sensors on the A272 engine and it looks straight forward, but there is nothing specific about the newer 4.2L V8.

So has anyone else had this issue on the 2004+ XJ8 V8 engine and can offer any advice.

Prior to the reduced performance warning the engine had been idling rough a couple of times at startup but once was warm and revved a little it passed.

I may if time allows, post a proper writeup and photo's of the experience.

 

Hi trosty,

I don't know if you've checked the Workshop Manual for possible causes of the P0327 code, but one of them is "Poor sensor contact with the cylinder block," and another is a short to ground in the sensor wiring harness, so it's possible you don't actually need a new KS. The manual gives Pinpoint Test details for determining the cause of the code.

Please let us know what you find.

Cheers,

Don

 

I hadn't researched the code in the manual when posting yesturday. I posted it directly after checking the OBDII reading. It does open other avenues though for rectifying the issue.
However, after carrying out other tasks yesturday (oil change and running light to LED change) the warning has not returned. I did get my fingers in there and have a wiggle of the sensor cables.

I will research it more as you suggest via the manual and see what the real problem is.

 

After the appearance of this in March and the wiggling of some wires in the engine bay, as you are aware it disappeared. Today it has returned.
I will once again get into the engine bay and try to be a little more investigative and try and diagnose the issue. It has been raining a lot here in Dallas lately and it may just be some sort of water seepage into a connector somewhere (as I have no under belly covers).
I will keep you all posted.