hey guys. my car is 2011 BMW M3 at 2500km
there is a werid (ding ling) metal noise coming out from my engine when im driving around 40km/h after i pass 40km/h its gone. some times i got the noise at 10km/h.
i took to the dealer and they said its cuz of the gas that im using. i was using esso 91 since i got the car. i refuel my car last monday, and at that day. i started having this problem...
anyone else ever had this problem before??