Lately I've noticed smoke from my exhaust. It only does this once in a while. Sometimes it does this when I'm heavy on the throttle and sometimes not. Anybody got any ideas on what it might be from? Thanks

 

does it puff out a lot of smoke when you take off after idling for a while? if so, valve stem seals...

 

Valve Stem seals. There is a guy in New York who does them for $2500. It will be worth the drive.

 

Check your ccv valves if bad replace them.. They will cause excess oil consumption and smoke trails. If they are good,, probably the exhaust valve steam seals.
Gatriel is talking about bmwoem1 from bimmerfest contact him ..

 

Thanks guys I will definitely check out CCV valves.