I am new to the forum here and I am looking for some guidance. I am out of options as far as I know at this point.

I have a 2005 Silverado 5.3 flex fuel engine Z71, and I am having an issue with the bank 2 knock sensor. I have replaced sensors twice and wires, the engine only has 4k miles on it, the fuel pump was just changed this past weekend, and I only run 93 octane fuel. After all of this to no avail on the issue of the knock sensors, I can clear the code and it will be back on within 30 miles. I have no clue where else to look or what else I can do to resolve the issue, also I do not believe the PCM is failing because I have no other symptoms pointing to PCM failure. Any and all advice on this issue would be greatly appreciated as I am stumped currently

 

Not sure about a 2005, but I had a '95 454 with a knock code. Turns out, the knock sensor control is inside the ECM. replaced the sensor with no fix. Changed the ECM with a used one found on E-Bay and all is well. Replacement was from a Tahoe 350, but I used the old chip and all is fine.

 

to the op
You have not ruled out a pcm by any means. Other than thinking its working properly what have you done to rule it out? Here is one option for you to consider. Maybe the system is operating normally and picking up an actual knock in the engine.

I have not read the diagnostic for this vehicle so this may or may not apply. I have seen on newer gm vehicles where the system was working properly, but there was a knock in the engine, that was audible that set a knock sensor code. Posting the actual code would help determine the fault.

 

I also have a 'knock sensor issue' on my 2005 5.3 (non-FF) Silverado.

I just use mid-grade gasoline.

No more codes.