Another LS1 knock sensor issue (after replacing)
03-03-2012, 08:16 AM
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Another LS1 knock sensor issue (after replacing) 02 Silverado. Truck started throwing a P0332 code (whatever the rear sensor code is) Being proactive I replaced both knock sensors with ones from Ebay with the GM part # on them and a new GM harness.
I put the thing back together with care. No pinched wires etc. Now I get a code for both sensors, 332 337. If I measure from the harnes going to the sensors to ground I get around 100K ohms on both. That tells me there is no short and both readings are identical. Before I go and buy new sensors, is there something I'm missing? I reset the codes and they show up again in the recent codes within 5 minutes of driving.
Are the sensors crap? Common sense says they might be since I now have both coding.
Thanks!
I put the thing back together with care. No pinched wires etc. Now I get a code for both sensors, 332 337. If I measure from the harnes going to the sensors to ground I get around 100K ohms on both. That tells me there is no short and both readings are identical. Before I go and buy new sensors, is there something I'm missing? I reset the codes and they show up again in the recent codes within 5 minutes of driving.
Are the sensors crap? Common sense says they might be since I now have both coding.
Thanks!
03-03-2012, 09:14 AM
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I would say they are crap, I tried using cheaper knock sensors and they never lasted. Also did you torque them properly? I know it sounds stupid, but if they are too tight they might be vibrating around too much. Just a thought.
03-03-2012, 09:33 AM
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Both sensors torqued to 15lbs. Funny thing, I took my old harness and plugged it in, tried a combo of the old sensors and locations on the old harness and connected the senor to ground and it still coded on both. You would think at least one would check out ok.
Good thing is I have a scanner and can clear in the driveway. No driving needed as all you have to do is high speed idle > 1500RPM for several seconds. So wth is going on....
Good thing is I have a scanner and can clear in the driveway. No driving needed as all you have to do is high speed idle > 1500RPM for several seconds. So wth is going on....
03-03-2012, 10:10 PM
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That's a day I will never get back !!!! 
Both sensors were crap. I bought two sensors off of Ebay. Excellent deal, advertised as new, appeared to be new, have the delco numbers on them and ohm out fine but are as deaf as can be. The seller sells many parts but I'm scratching my head on this one. China garbage? Lots of fake Delco stuff out there. Let's see if he makes good on a refund now that I had to obtain others.
Here's a troubleshooting tip for you. You can ohm sensors on the bench and tap on them. If the resistance changes as you tap, I said tap, they are alive. These did not budge and that was my clue. I hated removing the intake again but I chased everything and finally the sensors.
Back to normal now.
Both sensors were crap. I bought two sensors off of Ebay. Excellent deal, advertised as new, appeared to be new, have the delco numbers on them and ohm out fine but are as deaf as can be. The seller sells many parts but I'm scratching my head on this one. China garbage? Lots of fake Delco stuff out there. Let's see if he makes good on a refund now that I had to obtain others.
Here's a troubleshooting tip for you. You can ohm sensors on the bench and tap on them. If the resistance changes as you tap, I said tap, they are alive. These did not budge and that was my clue. I hated removing the intake again but I chased everything and finally the sensors.
Back to normal now.
