Originally Posted by BMW Fanatic
What year's the car? Warranty? If that stuffs still in tact then why you worried bro. Unless you're supercharged or gotta tune to worry about.
Piston rings are a decently cheap fix. Cracked block is more expensive but very unlikely. I bet its not so bad. A lot of little leaky things or worn things can cause this. My bet is on the piston rings or seals. good luck!