Surprise! I'm back!
This is going to be a quick one so I didn't want to open a new thread...
I'm reluctant on this one because I think I already know the answer...
There's gurgling/boiling noise coming from the exhaust after the motor has been shut off! There was also some liquid which I can safely assume is coolant 'splattering' out of the exhaust... There's some crackling/popping noise coming out the exhaust at idle but up front the engine sounds smooth and It drives fine...

Blown head gasket???

FYI I just got done sealing up the exhaust system, could the back pressure difference been enough to blow out an already deteriorating seal?

Btw, the oil is clean...