As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
PREMATURE EXHAUST VALVE WEAR DETECTED BY LOW COMPRESSION/ EXHAUST VALVE LEAKAGE. EXCESSIVE WEAR STEP FOUND ON THE FACES OF THE LOW TIME EXHAUST VALVES. THE EXHAUST VALVES FROM ALL 4 CYLINDERS ARE AFFECTED. FURTHER ENGINE EVALUATION IN PROGRESS.