P0332, Knock Sensor Low Voltage

[chriskat01]

My first post, I have this issue and am looking for assistance. I have this code, so far I have replaced both knock sensors. First time with Advance Auto parts, including the pigtail. Second time with AC Delco sensors and pigtail. Both times the code reset within a day or two. I've checked the wires and can't find anything obvious wrong, they have zero ohms end to end and I can't make them short to ground. I replace the ECM. Still the code reset within a day or two. I'm thinking of cutting the wires at both connectors and splicing in new wire from end to end. Any other ideas?

Thanks,
Jeff

 

[Fless]

Tell us more about your truck: make, model, year, engine, etc. Bet it's not a 2021+.

EDIT: temporarily moved to 2000-2006 section until OP confirms year.

 

[OR VietVet]

Welcome to the forum. It certainly would help to know the vehicle info. I am guessing a 2000 to 2006, but that is just a guess. When you say which code, which code(s) are we talking about. You have already shot the "parts cannon" at it.

 

[Joseph Garcia]

Welcome to the Forum from NH.

Lots of knowledgeable folks here who freely share their knowledge, experiences, and perspectives. Knowledge is power.

I hope that you will become a participating member in the Forum's discussions.

More detailed info, please.

 

[chriskat01]

Sorry, correct not a 2021+. It's a 2005 Yukon XL, SLT. 5.3 litre. The code is always P0332. Thanks for any suggestions

 

[OR VietVet]

Since it is USUALLY a knock sensor, harness or ECM/PCM, then I would suspect the harness at the ECM/PCM to knock sensor harness.

 

[nick0789]

I do not know you skill level / knowledge base so I apologize if any of my ideas come across as dumb to you:

- do you still have the original harness to re-install, to confirm whether the harness is the culprit? I don’t suspect it to be the harness, personally, but it’s probably worth performing a sanity check on it
- what did you torque the knock sensors down to?
- have you swapped knock sensors (front to back, back to front) to see if P0332 populates or if you get P0327 instead?
- are the threads clean on the engine itself?

When I replaced my knock sensors earlier this year (as part of the intake manifold gasket job) I swore I torqued everything down but my rear knock sensor was only snug tight … not that “snug tight” is much different than what’s specified but still. And of course I pulled the plug and cracked the ceramic top so I had to replace it anyways.

Hopefully you get it figured out soon!

 

[chriskat01]

Thanks to everyone.

I do not have the harness any longer but I have replaced it twice now, of course that doesn't mean they were both bad but three (including the original) harnesses have produced the same code.

I also have not swapped the sensors front to back, I thought about that but it's a lot of work and two new sensors have produced the same code. Probably worth a try.

I torqued the knock sensors to 15 ft lbs, actually 180 inch lbs because my ft lb torque wrench won't go below 30.

Does anyone know if there is any "interruption" in the wire from the connector at the intake manifold to the connector at the ECM? I'm wondering if that wire could be broken or intermittent somewhere along the way but I'm not sure where that could be.

Thanks again.

 

[rockola1971]

P0332 denotes Knock sensor bank 2. Bank 2 wire is Light Blue. (Bank 1 should be dark blue). With engine running what kind of voltage reading are you getting off of both the bank 1 and 2 knock sensors? (Dont disconnect harness anywhere while taking reading).

 

[chriskat01]

P0332 denotes Knock sensor bank 2. Bank 2 wire is Light Blue. (Bank 1 should be dark blue). With engine running what kind of voltage reading are you getting off of both the bank 1 and 2 knock sensors? (Dont disconnect harness anywhere while taking reading).

I don't know the voltage I'm getting. I'll have to check. Any idea what the voltage is supposed to be?