Knock sensor replacement issues.

[Danzigman]

Well, I got the dreaded check engine light telling me I had a bad knock sensor. I read everything on here and other places before starting the job. I got the factory gm gaskets, harness and sensors. I used ACDelco 213-3521 sensors part number 12589867. Once I tore everything down, I found that the rear sensor was rusted. The front sensor looked new, but I replaced it any way. I found that the part number was different on the original sensor, so I searched and found that the original part number was replaced with the one I had. I cleaned out the rear hole as best I could. I reinstalled everything and made the suggested rtv C formations around the sensor holes. I did rtv the sensor plugs upon installation, other than that the only other possible issue was that my large torque wrench started at twenty foot pounds, instead of the required 15. The torque wrench i used for the intake was a 1/4 drive so I couldn't use that for the 22 socket. This being the case i installed the sensors at 20 foot pounds. The sensors were never dropped or anything. It took 149 miles before the light returned for the first time. What could be the issue? Could it be the 20 foot pounds torque? If so why is the front sensor not trowing codes?

 

[David Paul]

Watching as I'm about to replace mine......

 

[Junior_22g]

Check that video out. I watched that and its got alot of great tips for this job!

Make sure your connections are all tight on the harness. I just did this job on my 01 Yukon 5.3 a couple months ago.
I dont see the torque being the issue. I bought the correct wrench from Sears to do mine but me being me, I heard the click from the wrench and went a bit tighter. The torque specs are also there so you dont over tighten and strip or break the knock sensor.

One thing i noticed is that during cleaning out the sensor cavities, some of the rusty mess fell into part where the sensor screws in. I took a can of air and blew it out. Make sure those areas are clean too.
The last possibility is that you may have gotten a bad part. Sucks, But it's possible.

Let me know if you have any specific questions.

 

[Junior_22g]

There was mine in all it's glory. Lol

 

[Junior_22g]

And going back together.

 

[pnwdan]

i would just rtv the plugs not all over the plate

 

[bottomline2000]

Yeah, this is how i did mine and I wouldn't want to over torque the sensors..I have a sears 3/8 ratchet with a 1/2 adapter that can hit that torque figure. Goes down to 10ft lbs. Lucky they didn't strip.

Sent from my SAMSUNG-SM-G900A using Tapatalk

 

[Danzigman]

That is the video that I watched. Now I am up against the wire. My inspection is due at the end of the month. I hate to repeat the process just to have the same issue.

 

[Danzigman]

Check that video out. I watched that and its got alot of great tips for this job!

Make sure your connections are all tight on the harness. I just did this job on my 01 Yukon 5.3 a couple months ago.
I dont see the torque being the issue. I bought the correct wrench from Sears to do mine but me being me, I heard the click from the wrench and went a bit tighter. The torque specs are also there so you dont over tighten and strip or break the knock sensor.

One thing i noticed is that during cleaning out the sensor cavities, some of the rusty mess fell into part where the sensor screws in. I took a can of air and blew it out. Make sure those areas are clean too.
The last possibility is that you may have gotten a bad part. Sucks, But it's possible.

Let me know if you have any specific questions.

I watched that video as well before starting the process. Not sure what i did wrong.

 

[pnwdan]

I watched that video as well before starting the process. Not sure what i did wrong.

Did you say you put RTV in the plugs?