As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
(CAN) PRE-INSPECTION RUN-UP, FOUND THE ENGINE RUNNING ROUGH AT IDLE. COMPRESSION CHECK FOUND NR 1 AND NR 2 WITH LOW COMPRESSION. THE CYLINDERS WERE REMOVED FOR INSPECTION AND THE CAMSHAFT LOBES WERE FOUND WORN. THE INTAKE LIFTER ON NR 2 CYLINDER WAS ALSO FOUND WORN. THE ENGINE WAS REPLACED.