As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
(CAN) PILOT REPORTED A ROUGH RUNNING ENGINE. INITIAL INVESTIGATION FOUND THE HYDRAULIC TAPPET BODY AND SYSTEM HAD FAILED ON THE NR 4 CYLINDER INTAKE SIDE. THE ENGINE IS BEING SENT FOR TEARDOWN AND INVESTIGATION. FURTHER REPORT TO FOLLOW.