Here’s my work-in-progress. I’ve always wanted a BMW and got the fever for a 335d. After a long search I found a 2011 with 37K miles, clean Carfax, one owner. I bought it from an independent who deals only with low-mileage BMWs (former dealership guys). It’s still under the new car warranty. I went into this with my eyes open about CBU and maintenance, although I wish my eyes had been open even more. Eight weeks after purchase, on a 300-mile highway trip the SES light came on and it ran rough. Called BMW and they said it was safe to drive it home. Turned out to be a failed injector and drove home 150 miles on five cylinders. That was fixed under warranty. Two months later another SES, although no obvious drivability problems. This was a couple of days of reprogramming, and another new injector, under warranty. Another month or so and another SES light. This time the dealer did a walnut blasting under warranty. But when they put it back together they heard noise and there was vibration on the test drive. Speculation that a piece of carbon was rattling around in the head. They need to keep the car and fix the new problem. So now the engine is out of the car; the head is off the engine; the cams are out, all the valves are arranged on the workbench. They need a tool from Germany that’s back-ordered so it will be at least two more weeks. I’m driving a loaner X3 diesel (pretty nice). The dealer has been good through all of this – I have no complaints (except that I will have been without my car for 5 weeks). It’s covered, and just before this happened I bought a three-year extended. But my confidence in this car is really shaken. I've put 4,000 miles on it and it's been in for work for nearly a month total in eight months. I have a feeling that despite all this major work (it has to be $12K or more) that damn SES light will return. Despite the great pleasure of this car when it’s working, I think my diesel experiment will be a one-time thing.