Mechanics

CHEVROLET TAHOE KNOCK SENSOR PROBLEM

2001 Chevrolet Tahoe • 200,000 miles

My Tahoe 5.3L had code p0332 and p0327 both KS. I replaced and replaced the harness. Cleared codes light came back on same codes. Replaced with reprogrammed pcm again light comes back same code. Checked resistance is good through wire all the way back to pcm went ahead and spliced in new wires from pcm to ks harness plug. Again still have ks codes. Pulled intake took out knock sensors retorqued and still have codes for both ks. I am at a loss here what to do the pins for the pcm are good both male and female and doublt I have 2 faulty pcms and 2 faulty Knock sensors that were new? The only thing I have not tried is to go with delco KS instead of aftermarket but why change if I get good resistance? I am not sure how to check voltage for these since its a 1 wire setup for each ks I assume the pcm sends a signal and grounds as well? Anyway any advice you have I would appreciate it greatly. I have no other codes occasionally I will get a evap malfunction code but do not think these are related. There is no engine ping or knock either runs fine.
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Bk26008
October 25, 2012.



Thereis a tsb on this you have to build a siliicone shield around knock sensor or it willgive same codeagain. I'm including pics and hope you can enlarge enough to read.


Hmac300
Oct 25, 2012.
I have already done that as well.


Tiny
Bk26008
Oct 25, 2012.
The damn you built is only supposed to go around the back side and not completely, also the foam on theintake manifold is supposed to be removed. I don't know if yo have done that as well. One other ting I hfound in tsb is the ground for pcm on right cylhead either at frt or rear is corroded, you have to clean all contact areas and then put a protective over it to stop corrosion. I can't think of anything else to tell you knock sensors don't operate by resistance they operate by something else which I can think of.


Hmac300
Oct 27, 2012.
Yea got the silicone dam correct and yes they do have a resistance value which both spec out 99k on ohm scale. I will take a look at the grounds. I think that I read somewhere people were having issues using an aftermarket part instead of ac delco?


Tiny
Bk26008
Oct 27, 2012.
I didn't see that but it wouldn't surprise me alot of these parts made in china are crap


Hmac300
Oct 27, 2012.