Anybody else have this problem? The o2 sensor on my passenger side cat will not stay tight. Any suggestions?

 

Bump

 

Some blue threadlock?

 

I'm having this issue with both of mine, and its with the non-fouler/spacer.. but basically the same thing. Non-foulers are stainless steel. I used some blue-threadlocker and still same issue.

Going to try cleaning them up again with a wire brush, and also cleaning out the high flow catalytic converter threads.. and give it another go with thread locker.. Any other suggestions?