I have noticed this for a couple years now-- a buzzing/rattling sound coming from my R53 (125k miles now). does it at most speeds when accelerating (not when speed levels out or when clutch is engaged). No codes, engine compression levels normal, no leaks, or other issues (that I can tell). Engine runs fine. sounds like it's definitely coming from the front end, maybe left side. do not know what to think or where to start searching (again). Have had the car up on jack stands and gone under looking for loose components, but everything seems good. Any ideas/leads are appreciated. :mad2: