09/07/2026
This is not a pretty picture.
This catastrophe was most probably caused by an un-diagnosed loose or dropped valve seat, which is not uncommon in the M96/M97 engines. A broken valve spring can also cause the same result, but in this case the valve springs were fine, although the cam follower button and valve stem top showed significant wear caused by excessive clearance.
I'd be surprised if there was no noise or clicking.