Alright a have a very strange problem here. It only happens when the temp gets to be a about 70 deg outside and gets worse the hotter it gets. There is a drawn out drone sound that is coming from the engine area that happens after i shift when accelerating and building up boost. It happens immediately after i shift or let up on the throttle. When its cold outside it doesn't do it at all. The only mods i have is the res delete and a different air cleaner. Any ideas what this is.