Hello guys, I am getting desperate to get rid of a weird noise from the engine of my F20 m135i 2013.
The noise is from the right side of the engine bay every time when i stop the car. Noise recorded as below video. It sounds, to me, like... rolling marble on a piece of glass. It is very annoying as i can hear it very clearly inside the cabin.
https://www.youtube.com/watch?v=Hi8ktwM1U84
It happens only when the engine is warm.
It lasts for 5-10 seconds after the car is stationary and then it disappears. During the noise if i put the gear in N or P, immediately it shuts up. If I put the gear back to D, the noise happens for 3-5 seconds.
It happens again the moment my foot off the brake and the car starts creeping. Then revving it above 800~1000rpm, it disappears again.
It only happens in 1st gear.
And then sometimes maybe the engine gets really hot (like after some aggressive driving), the noise could happen when in sport mode even it is in P gear. (like the video)
Recently i find it more likely to happen when the car is up-hill. When down-hill, the car stops without any noises.
Other than the noise, the car runs perfectly fine. Idling is smooth. Gear changes are smooth.
This has been bugging me for months... any ideas?
Thanks in advance!