occasionally at idle i get this howling from around my TB.... i thought maybe it was my new serpantine cause i replaced one serpantine and then it immediatly got chewed up because of a loose tensioner but we tightened the tensioner, replaced the belt again, and as far as i can tell the belt isnt rubbing, but i sometimes get this howl, and i notice that my boost gauge goes from around 20 vac to like 22 vac during the howl.... maybe a vac leak of some kind?