white smoke oem cats?
 

I put my stock cats back on after removing my cnt high flows and when I started it up and let it run for a few minutes white smoke started coming out from under the hood. Everything is tight and I can't seem to find where it's coming from or why it's smoking.

Did you use any penetrating fluid to loosen the bolts when swapping cats? Can you smell raw exhaust fumes? That is really the only thing I can think of as even if there was an exhaust leak, you wouldn't be seeing any white smoke.

I had to drill out the demon bolt that broke off and that might have had some wd-40 left on it. So it should just go away after driving a bit?

Sounds like WD40 burning off. It'll burn off a whitish smoke and have a distinct smell. It will go away in a couple days.

I agree with what Q8 said, sounds like you just have some residual WD40 burning off and should go away after a couple drives at most.