Knock Sensors -- Why do they keep going bad??

[Mighty Hd]

Vehicle: 04 2500hd 6.0 4l80E w/ nelson's 89/93 tune; TM/abuse removed, etc. 18,105mi.

Seems that I can't keep the knock sensors for longer than 5-8,000 miles. I've had three replaced under warranty so far and now this current one (Number 4&#33 is bad again.
SES light on saying low voltage.

I checked the connections (dealer said Friday the connection was loose---I say bs its fine) and they're tight as nats nuts on a cold day.

No water on the engine in about 4+ weeks from the last time I washed and detailed it.

What can the cause be from these things going bad so often? IT's getting really frusterating.

Thanks guys!

[RedHeartbeat]

Get Allen to turn the sensitivity down on them on your next tune.

[Mighty Hd]

Would that require having to relearn the crank angle, etc?

[OldSkool69]

Related to this post, not electrical at all, I had this issue with 3 Engines 5.3L.

Each have more than 100.000km, and they all killed the back knocking sensor. They reason was that where the Knock sensor is located, was ful of crap and water and all shit.

The sensors were fully corroded, and no conectivity whatsoever!!!!

The Ruber housing was Toasted in meanings that it looked OK but it was HARD as wood. No dealer here had those housings, so I resolved it with a nice Black EURO silicon paste to weather tight them.

Been at the opening I also worked the front ones, even if they dont looked affected.

So far it has worked. But still think is a material falilure or miscalculation from GM

[Mighty Hd]

Is there any way to get it off without having to remove the upper manifold?

I can pick one up for $30 online ..if it's an easy swap I'll do it myself. Any time involved I'm letting the stealership under warranty deal with it.

It's a real pain in the ass to get it to the dealer.

[Mighty Hd]

Well I swapped in the stock pcm--could NOT get the light to come back on--tried 3 complete driving cycles, etc.

I put the nelson tune back in and sure enough the light is gone there as well.

I wander what the deal is?

[GBs_03]

<div class='quotetop'>QUOTE(Mighty Hd &#064; Sep 25 2006, 07&#58;28 PM) [snapback]66530[/snapback]</div>

Well I swapped in the stock pcm--could NOT get the light to come back on--tried 3 complete driving cycles, etc.

I put the nelson tune back in and sure enough the light is gone there as well.

I wander what the deal is?
[/b]

Could it have been a bent or dirty pin in the tuned PCM?

[Mighty Hd]

<div class='quotetop'>QUOTE(GBs_03 &#064; Jan 1 2007, 07&#58;35 AM) [snapback]77961[/snapback]</div>

Could it have been a bent or dirty pin in the tuned PCM?
[/b]

I checked that as well.

Since my previous post they have been replaced.

The check engine light is on AGAIN with a knock sensor low voltage code again.

Going to the dealer for another replacement. This will be set #6 in 20,000 miles.

[RedHeartbeat]

Did all that start with the custom tuned PCM? It may be just a defective PCM, sometimes they go bad. You may have to get another PCM sent to you to see if that is what is causing your problem. Doing a crank relearn is not a big deal if it gets your problem resolved.

[Mighty Hd]

It started before the tuned PCM.