So 2 weeks ago I installed an EPM o2 dump. Today I was doing couple things by the car and for the heck of it, I checked if all the o2 bolts are still on tight. To my suprise ALL of them were not

I mean when I installed the dump I tightened the heck out of them, my brother in law even tried and they were on TIGHT. But today everything was loose

 

two things to look for....

Things get loose because of vibration, and the expansion and contraction due to heating and cooling. You need to get a set of cupped washers.

Also if you are using the stock bolts, check to make sure the bolt is tightening against the O2 housing flange. Some times the bolts will bottom out against the shank of the bolt not the flange.

 

They are loose because when you initially tightened them, they were cold. Anytime you're tightening something that experiences hot/cold temperature changes, you have to initially tighten it when it's cold, then run it so it heats up, then tighten the bolts again.

In your case, tighten them back up - then take the car for spirited drive. Get the bolts nice and warm - then tighten them again. 10 to 1, after you run the car, you'll be able to tighten them up a little more.

 

Bingo. Heat will cause bolts to loosen up after being cycled. The guys above hit the nail on the head.

 

there should be a torqe sequence for it..torqe them

 

hmm these o2 housings seem to be having problems.my buddy had tons of problems with his.i tried to help but the thing was just a mess.