Safe to ingore P0327 & P0332 - Knock Sensors?

With the help of these forums I've been able to track down the gremlins in my LS swap (LQ9 and 4L80e), but I have two remaining DTCs that I haven't been able to clear up:

0x10: P0327 - Knock Sensor 1 Circuit Low (Bank1) (Pending, Current)
0x10: P0332 - Knock Sensor 2 Circuit Low (Bank 2) (Pending)

From what I've read, these indicate that the average voltage of the knock sensor signal is lower than expected, and this is probably because I'm running some ebay sensors. I did test them and they show ~100kOhm resistance and do respond to impact by producing AC voltage.

Instead of replacing the sensors right away I'm planning to turn those DTCs off, because I've read that when they're set KR is affected. [Edit: I do see KR!]However, I'm not seeing any KR right now so I'm not sure if that's true.

So my questions are:

1) Is there any ill effect of disabling these DTCs?
2) Is there any ill effect of not disabling but ignoring these DTCs?
3) Is there any way to calibrate the PCM to these sensors' average output voltage?

Thanks in advance!

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There is tons of knock in that log, where are you not seeing any? That log is something else, I see lots of weird stuff going on. Massive timing pulls, the MAP sensors pegs out at 100kpa kinda often.

Yes you can shut the codes off to stop the timing pull because of the current DTC's.

Early gen 3's have issues with this often. I recommend new GM knock sensors, torqued properly is a must, new knock sensor harness.

If you want to delete them in the mean time set them to no error reporting and also set max knock retard PE and non PE to 0. Cars did make it decades without knock sensors but you would be better if they were working. Be careful about knock.

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Originally Posted by 5FDP

There is tons of knock in that log, where are you not seeing any? That log is something else, I see lots of weird stuff going on. Massive timing pulls, the MAP sensors pegs out at 100kpa kinda often.

Yes you can shut the codes off to stop the timing pull because of the current DTC's.

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Hey thanks, really appreciate the response! I do see KR when I view the data as graphs but I was watching the logged values and didn't see it as a result during collection.

It looks like both KR and MAP at 100kPa both coincide with me flooring it while parked. Is either of those an abnormal response? My tune is stock for a 2004 Silverado SS except for some changes unrelated to engine parameters.

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Originally Posted by Alvin

Early gen 3's have issues with this often. I recommend new GM knock sensors, torqued properly is a must, new knock sensor harness.

If you want to delete them in the mean time set them to no error reporting and also set max knock retard PE and non PE to 0. Cars did make it decades without knock sensors but you would be better if they were working. Be careful about knock.

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Thanks, trying to understand the suggestion for setting KR to 0 -- is this under the assumption that the knock sensors are not working at all? I think they *are* working, just at a lower average voltage than spec. So I believe they can correctly detect knock but are less sensitive to it, which means that KR is less likely to kick in vs. more "accurate" sensors. If that understanding is correct, than I should be ok to leave KR alone since it's unlikely to kick in. Does that all make sense or am I off the mark here?

Zeroing out those tables. Yea don’t do that. Knock sensors usually work even when they set 327 and 332 codes. Just set the DTCs to NER.

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Originally Posted by 2xLS1

Zeroing out those tables. Yea don?t do that. Knock sensors usually work even when they set 327 and 332 codes. Just set the DTCs to NER.

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Yesterday I finally set the DTC's to NER on my 100% stock 04 Avalanche tune and left the knock sensors working. Been getting P0327 and P0332 DTC's for a couple of years now. Replaced Knock Sensors and Harnesses 2x with no difference - used GM knock sensors. Checked wiring between knock sensor harness and PCM pins with an OHM meter and visual. Replaced knock sensor harness connector (top of engine) with a Deutsch DT series connector. Finally replaced PCM. Still the same. Would set both codes at random 45-65 mph cruise in overdrive during second key cycle if the cruise was occurring. Even bought an oscilloscope and watched waveform while tapping on the engine and while driving - no smoking gun. I suspect problem is something mechanical in the engine making noise and screwing up the minimum noise level learn that the PCM does - I think it updates minimum noise level each key cycle that it meets conditions. https://forum.hptuners.com/showthrea...ighlight=p0327 Then when engine gets quiet during cruise, noise drops down far enough to set the codes. Of course this is only speculation. I do have some piston slap when cold on my old engine, but otherwise is fine. As long as that f***ing light is off, not showing codes pending, and it's not rattling - then I'm good. I should mention that KR is zero except 4 degrees sometimes shows in the table at 4000 rpm under full throttle. I suppose that could even be a loose bearing or something other than a real knock - but it does illustrate that knock sensors are working with the codes set to NER. Comments?

p.s. I have been using HP Tuners VCM scanner for about 6 years, but paid the 2 credits and updated to VCM suite for the purpose of making this one change in my vehicle. So I'm a newbie to VCM editor.