What oil are you using?
You do know new vanos has a break in period, right?
The timing chain guides haven't seemed to give us any issues yet...at least, I can't recall reading of one go bad...at least not in NA engines, so I wouldn't worry about that.
The exhaust mani heat shield (riveted onto mani gasket) seems to rattle. Exhaust components might too (the front bracket seems to rust apart).
Could be pulleys beginning to complain.
Upcoming NYC dates: Jan 8 and 27. See Facebook for other shows and PM me if you can make one...love to see you there!
Mangofy your E46!