I have 08 e93 m3 at 69000 miles and I have been hearing weird metal rattling/chirping noise at around 2000~3000 rpms at acceleration.
Below is a video upload from another m3 owner having same issue. You can clearly hear it from 2 seconds ~ 8 seconds.
I took my car to several independent BMW shops but they were unable to nail it down. So I took my car to Southbay BMW. At first, foreman went driving with me and his opinion was engine knocking. But I wanted to make sure what it is so left it for a full diagnose.
And guess what? They kept my car for 13 days and concluded it was not engine knocking and it's just a normal sound from M3
and yes...I ended up paying $195 to the stealer for nothing.
This sound happens at almost every gear now and is very annoying. And it's more distinguishable during summer and uphills.
Can anyone identify this noise? Truly appreciate it.
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