PCV? Fahgettaboutit. It's just held in by friction. Can't see it retaining enough pressure to hiss. Besides, if you've got that much blowby you would see the smoke billowing on startup before the cats heat up and hide the oil burning.

It would have to be a heck of a vacuum leak for you to hear it over the engine noise.


So my money's on LittleBeast and the exhaust leak idea. Let us know what it was!