Originally Posted by vasillalov;126****3
So it looks like you fell for the OCC "scam" as well, didn't you
The facts about OCCs are as follow:
1. Not a single Oil Catch Can can capture 100% of all oil fumes without choking the PCV system. Yes, they help, but again, not one of them will give you 100% efficiency.
2. The Oil Catch Cans work ONLY during times when there is boost! That's how the PCV check valves change the flow of the air. During cruising AND deceleration, the fumes do not go through the OCC.
Also, there are two check valves that can go bad. One is integrated into the valve cover itself and one is in that little tube that goes to the back of the rear intake tract.
Rob@RB sells upgraded PCV check valves for the one that screws into the valve cover itself. Users are reporting good results with those.
Finally, I've noticed that once the BMW factory oil gets about 3000 miles on it, the car starts to smoke more and consume more oil. If you have a fresh change of oil there is no oil consumption/smoking.
Hmm, interesting. I thought the same thing, as my car needed a quart at around 4200 miles, but I was losing a quart every 500 miles after that.
Turned out, the lower oil line to the rear turbo had a pancaked corner on the ring gasket which caused oil to spew from that corner. Fixed with a new gasket from BMW ($1.09) and 3100 miles later, haven't burned a drop of oil with nearly 100+ 3rd gear pulls going into 4th at anywhere from 18 to 20 psi on RBs.
IMO, if ANYONE is losing large amounts of oil (1qt in less than 1500 miles) you have a leak that needs addressing.