Hey guys, 2001 Tahoe 5.3, 4x4 , I need some mojor help. I changed out both Knock sensor because i was getting a bank 2 low imput code. Cleared the codes with a scanner and then codes 1 and 2 came on as (low imput). So I bought and installed the wiring harnest from the dealer and re-cleared the codes and they came on AGAIN. Both bank 1 & 2 low imput.. I have also tried clearing the codes by resetting the battery and it makes no difference. Does anybody know what else could be causing this problem??

 

Welcome to the forum. The knock sensor has a single wire going to the PCM. In order for the circuit to be complete, it needs to be grounded through its jacket/threads, provided the engine block is grounded to the chassis as well. Did you put some kind of sealant on the threads or something?

 

I moved this thread to the Tahoe section from the general tech area for added exposure...

 

No sealent at all. The weird thing is # 1 wasnt triping a code untill I replaced it while I had the intake off.

 

You can perform a search for "knock Sensor" and may find more info...

here is some info I posted a while back..

FYI:

Important: If the knock sensor is dropped, it must be replaced.


• Check the knock sensor for proper installation. A knock sensor that is loose or over torqued may cause the DTC to set.

• If DTCs P0327 and P0332 are set at the same time, inspect for poor connections at the KS harness jumper, located at the left rear side of the intake manifold.


Remove the intake manifold sight shield.
Disconnect the knock sensor (KS) jumper harness connector located on the left side of the intake manifold.
Set the DMM to the 400K ohm scale.
Measure the resistance of the affected KS using the DMM connected to battery ground.
Is the resistance of the knock sensor within the specified range?
93K-107K ohms



Here is the link to the other thread on the subject...looks like the harness may need to be looked at...
https://chevroletforum.com/forum/tah...-sensor-36494/