Knock Sensors

[StephenCasiday]

I am having troubles getting the knock sensor codes for Bank 1 and 2 to go away, I’m on my 3rd set of trying to replace them and have AcDelco stuff now, but before I put them in I tested the first set I put in that “didn’t work” and they tested fine, both read 99.7 Ohms and responded to “knocking” with a brass hammer and produced voltage. But upon using a SnapOn scanner you can see it isn’t outputting any voltage while in the truck and it’s running. Any advice here? 2005 LT Tahoe 4x4 5.3

 

[Tonyrodz]

I am having troubles getting the knock sensor codes for Bank 1 and 2 to go away, I’m on my 3rd set of trying to replace them and have AcDelco stuff now, but before I put them in I tested the first set I put in that “didn’t work” and they tested fine, both read 99.7 Ohms and responded to “knocking” with a brass hammer and produced voltage. But upon using a SnapOn scanner you can see it isn’t outputting any voltage while in the truck and it’s running. Any advice here? 2005 LT Tahoe 4x4 5.3

Have you changed the knock harness? If so did you use aftermarket or oem?

 

[selahpartners]

2001 Tahoe 372K miles strong... runs great, no knocking. Just a year ago I had the knock sensors replaced due to knock sensor and intake manifold leak codes being thrown. I used aftermarket as opposed to GM AC Delco. I just replaced the knock sensors and harness with AC DELCO... Is there anything else that is known to cause this issue? It seems to be a chronic issue. With high miles, and the engine being more loose that most on the road, it sure seems that would be some way of dampering the knock sensors or adjusting something in the ECM to allow for the high miles. It is a hell of a note when you cant get the thing inspected or registered when it runs just fine. I hope I dont have to move to a rural address to get outside the BIG CITY emission tests, just to be able to register my vehicle.

 

[nick0789]

Have you changed the knock harness? If so did you use aftermarket or oem?

To piggyback this, when I replaced my intake manifold gaskets I also did the knock sensors and harness. I did OE for the knock sensors and harness but immediately got a CEL. Knock sensors tested fine but had an issue with the harness. Ended up going with a Dorman harness and surprisingly didn't have any more issues. I'd double check the harness and consider swapping that if no one else has better insight.

I feel your pain. Removing the intake several times was a bit of a pain, but I got good at it.