Jump to content

Super Technical Knock Sensor Quest

Tom G

By Tom G
in 2000-2014 Silverado HD & Sierra HD

Recommended Posts

Daryl LBZ Senior Enthusiast

Daryl LBZ

Posted
Posted

 

Have you seen any engines with knock sensor's rusting out or with water damage doing it the manufacturers way?

Sure have. The used motor I put in my truck with 75k miles had both holes filled with water and a corroded knock sensor.

 

f7066fc80b059c68e4f3bc0431c33602.jpg

 

736c84434878852b0a1a008504173c3f.jpg

Daryl LBZ Senior Enthusiast

Daryl LBZ

Posted
Posted

But that looks like the "original" no RTV job, not the 3/4 circle of RTV that GM is now recommending...

Couldn't tell you for sure, I didn't really examine it that much when I replaced them. Definitely no water getting in now, and no sign of trouble due to completely sealing the hole.
  • 2 months later...
Tom G Enthusiast

Tom G

Posted
  • Author
Posted

You sealed it all the way leaving no space? And there have not been any issues that way?

Buckwheat Enthusiast

Buckwheat

Posted
Posted

Hi FWIW, I re-did my knock sensors. The ones I took out were throwing a code but actually didnt looks too bad, they had some white oxidation and the holes they went in just took a slight wiping out. They were not sealed in any way with RTV before I did this.

When I replaced them I was thinking along the lines of heat and used the Red rtv temp stuff. I coated around the outside diameter of the rubber plugs ( about halfway up...along the curved radius which would force rtv in the side walls). I then sealed the wire into the plug on each and around the outside of the plugs too.

While I was in there I replaced the intake manifold gaskets, and took that stupid foam piece out from the rear of the intake manifold...I left the front one in place. I used all ac-delco stuff after hearing the stories of folks having to back in there after using aftermarket stuff.

I havent had a problem since.

Personally I would be leary of coating the knock sensors with anything because they do work from the concept of sensing vibrations...if you should dampen that vibration with some kind of coating, you might find yourself going right back in there.

All the best!

Buckwheat

Archived

This topic is now archived and is closed to further replies.

Go to topic listing

  • Latest Articles

  • Posts

    • Atlas
      Acceptably cheap tires?

      By Atlas · Posted

      Which one, the AT or AS?   Starfire is made by Cooper/Goodyear but at $85/tire I'd think I'd need to level-set my expectations that they may not even be round 😉 But you're saying they're decent?   I'm already into this thing $1506 in parts, fluids, etc. Totaled all my receipts today. $250 of that was replacing an EGR and MAP sensor that were probably fine, but I'm not going to return the parts since they've been installed. I'm cheap, but not that cheap. I use it, I keep it!   I may or may not make money if I sell the truck at this point, but, that wasn't really the point. And if I billed my time, I'd be hosed for real. My thought on the tires is I "might" put 1,000 miles on before selling it. I just don't want to put absolute junk on it, that doesn't do anyone any good. If the Solus solidly isn't junk, I'll definitely consider them.        
    • rjgvt
      Is your l8t engine bay super dusty?

      By rjgvt · Posted

      I leave mine as is. I'm always a trip away from riding on unpaved roads. Dealer can clean it when they prep it after I trade it in for another new truck.
    • Grumpy Bear
      Acceptably cheap tires?

      By Grumpy Bear · Posted

      I have these on two vehicles and love them. Pepper is one of them 😉 
    • Atlas
      Acceptably cheap tires?

      By Atlas · Posted

      4WD. Far as I know it came stock with P's and not LT's. Definitely planning to put P's on it, but stock is a 109 XL load rating so I should probably stick within that guideline.   No rebates on anything I can see at the moment. Discount Tire is offering $50 off, but Pep Boys is very competitive on price, and also carries all the off-brand stuff. Les Schwab always wants an arm/leg, but they do good work.   It still has the original spare. Goodyear Wrangler RT/S, thing looks like a tractor tire LOL!! How times have changed.    
    • JohnRoy
      2020 Sierra 2500 windows rolling down

      By JohnRoy · Posted

      2020 Sierra 2500 HD (base model) gas engine 4wd.    All 4 windows roll down on their own. Happens somewhat randomly after stop and engine off - when engine turned off, when walking away from vehicle before or after locks activated. Pulled the window fuse F14 Instrument Panel Fuse Block Right; the driver's side still activates from driver's side door panel; passenger and back seat windows activate from local switches on their doors but not from driver's side group of switches. Power mirrors don't activate with fuse removed either (same fuse for both circuits). Problem not solved.    How can they even activate with fuse removed but they are all still opening and can control from each door?  When they open on their own, I can shut them from the switch in each door, but they don't stay closed.    Seems to be activated somehow with key fob; something bumping the key fob in my pocket or just handling - removed key fob and took it far enough away and now the windows stay closed. Replaced key fob batty just in case, no change.    Sounds like some kind of wiring short or maybe electronics. Dealer will first replace electronic control module without checking anything else and I anticipate problem will still exist since their troubleshooting skills are limited to "do whatever the computer says".  In any case, keyfob seems to be activating the circuitry.    Surely I'm not the only one with this issue, but I can't find anything related on the site. What do yall think?   JohnRoy  

  • GM-Trucks.com Clubs

  • Popular Contributors

×
×
  • Create New...