knock sensor - fix someones fix

Reply Subscribe

Thread Tools

Search this Thread

Oct 3, 2025 | 09:04 PM

kurzawa303

Thread Starter

Registered User

Joined: Oct 2025

Posts: 3

Likes: 0

knock sensor - fix someones fix

LM7 my knock sensors were not plugged in (used truck). I tested and and they were not responding to tapping on the block so I want to put new ones in and the one in the back broke off and then the screw removal tool broke off then the next one broke off so I took the valley pan off and someone has been here before and did this:

Any idea what this could be? it doesn't look welded but I don't get what this could be that would also allow a bolt from a knock sensor to screw in there.
Tomorrow I am going to try and "unscrew" it using a pipe wrench. My original plan was to weld a nut onto the bolt to unscrew it but if it doesn't unscrew then I have to deal with a nut being on there. The gasket at the bottom of the knock sensor portal in the valley pan is normal and undamaged so they would have had to put the knock sensor into this piece the normal way unless they cut the bolt off of the knock sensor and jbwelded it or something.

Also wondering if I should even deal with it or if I should just put the knock sensor in the back of the head, does that even work?
Would just the front knock sensor detect the knocks?

Last edited by kurzawa303; Oct 3, 2025 at 09:09 PM. Reason: Add pic

Oct 4, 2025 | 09:14 AM

Bbknucks

TECH Regular

Joined: Dec 2022

Posts: 444

Likes: 158

Part of the seal is still on there...

Might be able to get the threaded part out or you could relocate them to the gen iv location if you really need to run them