I have some experience with Bimmers dating back to the late 1960's, they're O.K. cars but always seem to have odd design faults like this that crop up after the car is over five or more years old .
My old shop partner's squeeze had a 2002 that was long in the tooth, every year it needed a valve job and since I wasn't allowed to touch it I never knew why .
I remember a lot of Bimmer owners had similar complaints : the car was fun to drive but needed more repairs than did the average old VW Beetle and no one worked on Bimmers cheaply unlike Air Cooled VW's .
On the other hand, I've been fascinated by Beemers since the early 1960's, the difference being well designed and amazingly well built Motocycles that don't have issues .
I expected to read an anti Bimmer driver/owner rant here
.
("what's the diff between a Porcupine and the average Bimmer driver ?") .