Never had any problem with my '97C280. 186,000 miles but I never have let a dealer work on the car because they usually come back with more problems. That said, I might suggest you buy a new gas cap as I once forgot to put mine back and expeienced a rouughness. With the new cap, car ran flawlessly. BTW why do so many MB's seem to leak oil? Mine never has and I would think the geniuses at the factory would figure this out. My 28 year old Chevy does'nt leak anything. What the deal?