Ladies and Gents,

2006 Silverado 1500 4.8L with 134K miles.

I've been looking at a CEL and code P0332 (Knock Sensor 2 Circuit Low) since February, and finally got around to pulling the intake manifold, replacing BOTH knock sensors with Delphi parts, and replacing the wiring harness to the knock sensors. Wiring harness was a Standard Motor Products part from RockAuto. I used red Permatex to seal around the caps for the sensors, and around the wires coming out of those caps, just to try and avoid another dead knock sensor. Then I cleaned everything up, put on a new set of Fel-Pro intake gaskets, and buttoned it all back up. Truck seemed to be running better with more pep than before, so I was happy. That was on Tuesday afternoon, and took about 3 hours for me, not having done it before on this engine.

I've also been chasing an EVAP system code (P0446), but that's another story. Yesterday, the ONLY code in the truck was P0446. P0332 was gone. As part of diagnosing P0446, decided to fill the tank up and also put some vaseline around the gasket on the gas cap, just to see it went away temporarily, since I understand the ECM doesn't test the evap system until it is down below 3/4 tank.

Darned if I went to check the codes this afternoon, and P0446 is gone, BUT I now have code P0327 - Knock Sensor 1 Circuit Low!!!!!!

What are the odds I have a bad brand new Delphi knock sensor, or bad wiring harness? Any way to test these knock sensors and the wiring harness from the connector that you can get to on top of the intake manifold, without going through pulling everything off again?

Thanks for any advice....

Jim