The frequency of the Reduced Power message on my 03 XKR is getting worse. I think I found the connector that the #1 knock sensor plugs into. It looks like it is located by the thermostat housing. The other knock sensor #2 is on the passenger side of the engine.

The knock sensor #1 plug is underneath the cooling hoses for the supercharger and under the hood Louvre. Water coming in through the hood Louvre could have gotten in the plug, if the plug seal was bad, and could cause the contacts to corrode. I tried to get this plug off so I could check the contacts, but the thing is on there real tight and I do not want to break it. It looks a little aged and brittle. Maybe a little WD40 would help get it apart??

I think it might be possible that if the contacts are corroded, it could give me the intermittent RP messages that only happen when the engine is hot and sits in the sun for about 1/2 hour. When I go to start the car I get the RP message almost immediately.

It occurred to me that if heat from the engine is causing the plug to expand causing a bad connection,due to corroded contacts, then when it happens again I should be able to spray the connector with circuit freeze and it should clear the PR message right away. The way it clears out now, is if I drive the car about 20 miles without stopping.

This may all be wishful thinking but it kinda makes sense and would be a lot cheaper fixing the plug, than replacing the knock sensors.

Has anybody had a problem with this knock sensor plug connector and if so what kind of error did it cause?

Bill N
03 XKR