Where are knock sensors on 2012 Chev tahoe?

[OR VietVet]

The o-ring is shown in the second pic if you scroll thru the pics. The right and left arrows in the pic.

It does make sense to me that no o-ring would be used so the metal is against metal to detect the pinging from the engine.

Maybe it is shipped that way to keep the bolt in place and instructions say to remove before install.

Two of the others show an o-ring but the rest of them at RA do not show an o-ring.

 

[iamdub]

The o-ring is shown in the second pic if you scroll thru the pics. The right and left arrows in the pic.

It does make sense to me that no o-ring would be used so the metal is against metal to detect the pinging from the engine.

Maybe it is shipped that way to keep the bolt in place and instructions say to remove before install.

Two of the others show an o-ring but the rest of them at RA do not show an o-ring.

Ooooooh! I missed the scrolling arrows. I see the O-ring now. Yeah, I'm pretty sure that's just to hold the bolt in place during installation on the assembly line and, in this case, in shipping. It's certainly not big enough to interfere with the contact area once the sensor is tightened down. It may even go into a recess machined into the sensor. If I think about it next time I'm under there, I'll check it out just out of curiosity.

BTW, @Richard Blakely, do you have a problem with yours?

 

[Richard Blakely]

Ooooooh! I missed the scrolling arrows. I see the O-ring now. Yeah, I'm pretty sure that's just to hold the bolt in place during installation on the assembly line and, in this case, in shipping. It's certainly not big enough to interfere with the contact area once the sensor is tightened down. It may even go into a recess machined into the sensor. If I think about it next time I'm under there, I'll check it out just out of curiosity.

BTW, @Richard Blakely, do you have a problem with yours?

The o-ring is shown in the second pic if you scroll thru the pics. The right and left arrows in the pic.

It does make sense to me that no o-ring would be used so the metal is against metal to detect the pinging from the engine.

Maybe it is shipped that way to keep the bolt in place and instructions say to remove before install.

Two of the others show an o-ring but the rest of them at RA do not show an o-ring.

 

[Richard Blakely]

Knock sensors have changed their positions on the 2012 version of the 5.3l v8. Prior to this year, you have to spend 2 hours and remove 65 bolts to remove the intake manifold to find that the knock sensors aren’t there. After purchasing a repair manual for this year, we found that they are located behind the oil dipstick shaft on one side and about the same position on the other side. It took about 10 minutes to replace. Wished I could’ve found this before the intake manifold removal.

 

[Richard Blakely]

I encountered a check engine light with the code pointing to drivers side knock sensor. Found also that it was encountered after filling up with 87 octane after 5 or so fill ups of 93 octane due to sluggishness accelerating. After knock sensor replacement, engine light disappeared and performance and mileage improved immediately on 87 octane gas!

 

[iamdub]

Knock sensors have changed their positions on the 2012 version of the 5.3l v8. Prior to this year, you have to spend 2 hours and remove 65 bolts to remove the intake manifold to find that the knock sensors aren’t there. After purchasing a repair manual for this year, we found that they are located behind the oil dipstick shaft on one side and about the same position on the other side. It took about 10 minutes to replace. Wished I could’ve found this before the intake manifold removal.

What repair manual do you have that showed a 2012 as having the Gen3 knock sensor setup? That's 6 years out of date!

Next time, just remember that TYF is all the repair manual you need.

 

[iamdub]

I encountered a check engine light with the code pointing to drivers side knock sensor. Found also that it was encountered after filling up with 87 octane after 5 or so fill ups of 93 octane due to sluggishness accelerating. After knock sensor replacement, engine light disappeared and performance and mileage improved immediately on 87 octane gas!

Glad you got that fixed! But, I'd have to suggest that you at least run 89 unless you drive it easily and are in a cooler climate.

 

[OR VietVet]

IMO, if you do like I would have done and many others here, the part would be looked at first and seen it was a different design and that would have made me dig in for the research as to why the part was different and therefore seen that the replacement process was not the same at all. Even as a tech and service manager for almost 40 years, if I am not 100% sure about a repair on mine or someone else's rig, I am going to do research for the job.

 

[Richard Blakely]

What repair manual do you have that showed a 2012 as having the Gen3 knock sensor setup? That's 6 years out of date!

Next time, just remember that TYF is all the repair manual you need.

Autozone had a repair manual for 2012-2015 (I think) that shows new location of knock sensors