I know this isn't the place for this but I've already posted in the truck forum and have not received a reply yet, hoping someone on here might be able to help.

So I have a 2006 chevy silverado and it is throwing a P0332, P2A01 and P2A04 codes, from what I found in the Trouble codes sticky is that it is a rear knock and a B1S2 O2 sensor issue. It will only throw the codes on start up, if I clear them out of the computer it will not throw them again until I shut the truck off and start it back up again. I did this on a trip from Midland to Fort Worth, reset the codes before I left. It never threw a code until I reached Abilene and stopped to refuel (about 150 miles) reset it again in Abilene and drove on into to DFW (about anoth 150 miles and it never threw the code again until I shut the truck off.

Having said all that I am concerned that the sensors might not actually be bad and replacing them will not solve the problem, and those sensors are not cheap. Can anyone tell me where all of the ground cables for this truck are located and how many grounds should be at each point?

I had an issue with water getting into the computer connections and corroding the terminals so I rewired all of the pins that were corroded. I used new pins from a spare harness I had, soldiered all the connections, shrink wrapped all of the connections, and wired them one at a time to make sure the wiring was in the correct place. Once all of that was done it went from throwing all kinds of weird codes to throwing a few codes. last week I found the ground wire on the passenger rear of the motor worn in two so I fixed it (again soldiering and shrink wrapping everything.), this corrected all but the above three mentioned codes.
Anyone have any ideas what might be going on??

 

had the same knock sensor issue on my Z71, turned out the harness under the intake manifold was not sealed and water got inside the hole the knock sensor is in. Your engine harness has 3 grounds that I know of, 2 behind the intake manifold and 1 below the driver side exhaust manifold twords the front. PM me your emain and I can send you some diagrams that point out the grounds.

 

Yea, I had the same issue with the knock sensor before as well, replaced it and put a small bead off silicone around the top of the seal to make sure it was sealed.
I'm thinking I can pull the knock sensors, swap them and see if it throws the code again on the same sensor, same with the o2 sensor. Hopefully that will tell me if its a wiring issue or a sensor issue. For some reason this truck eats o2 sensors, I've replaced the rear sensors 2-3 times in the past two years. I have extensions on the rear o2s but that should be causing the problem, I've put the extensions on other cars and never had an issue before.
Joe, I appreciate the response, I'm PMing you now.