As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
(CAN) DURING THE POST-INSPECTION ENGINE RUN SUBSTANTIAL ENGINE VIBRATION WAS NOTED. THE NR 4 CYLINDER WAS REMOVED AND THE INTAKE VALVE WAS FOUND TO HAVE A CRACK EXTENDING FROM A CENTRAL LOCATION TO THE EDGE OF THE VAVLE. SMALL CHIPS WERE ALSO NOTED TO BE MISSING FROM THE VALVE NEAR THE EDGES.