Had my 75k service done yesterday and while it was in they changed out either a PCV or diverter valve (I'm not sure which) at the same time.
When I drove it off, I thought that it sounded a little different under load/boost, but shrugged it off. -When I started this morning to drive to work, it sounds VERY different under boost... as if someone is blowing through a straw. -Hard to describe.
I'm still seeing normal boost on my boost gauge (peaking at about 15psi, typically holding in the 10-12psi range, but I've not tested that specifically) so I don't suspect a boost leak right at the moment.
I put a call in to my service writer, but I'm wondering if anyone else has experienced a similar thing, or if I'm concerned for no reason.
This is not related to excess-pressure blow-off or anything like that (I'm all stock in that dept) because it happens under sustained engine load, not on lift-off particularly.