Alright, several months ago I noticed a noise coming from the engine bay... sounds like a whistle or a buzz. I asked around and some said it's the turbo, but I'm not so sure. It's not burning oil, no smoke, and no loss of performance. I've tried two different BOV, and switched hoses on those, and the sound peersists. I was further securing my RoadRuns grille yesterday, and decided to screw around w/the BO one last time before I take it by a shop to track it down (and potentially replace the turbo). Well, I don't know what possessed me to try it, but before I hooked up the hose to the BO I blew into it as hard as I could... well, I heard a high-pitch noise! WTF!? From what I gather, that hose connects to the boost solenoid. Could that be the source of the noise? Enlightenment needed...