So after installing a new Bosch upstream sensor, and doing a full oil change, I've gotten some gray smoke coming from the passenger side of the block. It's not thick at all, if it wasn't for a red light I wouldn't even have noticed it. It doesn't really smell like anything, which is odd. It's nothing rubber, and it doesn't have that bitter burnt oil smell, either. I'm thinking it could just be the half a can of penetrating oil I used burning off the manifold and heat shield...hopefully. I'm about 99.9% certain the sensor itself is seated correctly, with no cross threading or leaks, and torqued down correctly.
So I guess the question is, has anyone else experienced the same thing after a new install? Or should I really get under it and see if I sprung a leak somewhere in between the manifold and lower portion of the block?
No new noises, either.