It probably wont fix it, already tried it earlier this week, made a thread..
http://www.xoutpost.com/bmw-sav-foru...idle-pics.html
Another thing im going to be trying this week is doing an oil change and going with 5w-20 Mobil1 Full syn,
I got the car at 63.5k and i changed the oil and filter at around 64kish with castrol edge full syn 5w-30, come to think of it, i dont think it smoked before my oil change when i got it which makes me think was there a lighter oil in there before?
Pnoy said another 4.8is person with same prob changed theirs to a lighter oil and it fixed it, cheap to try so i dont mind changing it again, im already 3k in on this oil and i plan on changing it every 5-6k so we'll see.
Edit: I actually hope you see this before you take it in tommorow, its extremely quick and easy DIY, if you can do an oil change or replace a filter you can do this.