: Hello, I was having the same problem with my car ,I found my oil seals around my timing chain tensioner were leaking. I replaced them and the problem went away. I still have alot of timing chain noise while the car is running but that is because the chain is stretched. I am going to replace it next week. You could have a worn plunger and spring in your tensioner, a week oil pump and or stretched timing chain. Check your oil pressure output first, then your tensioner.
: The tensioner is the cheapest fix and the easiest. due to the milage on your car you might as well replace the timing chain at the same time.
: It can be done from the top of the engine rather then removing the front cover's. But you must first figure out which master link you need to get from your local Mercedes dealership. Because BMW does not stock one.
: Good luck,
: Troy