As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
(CAN) CAREW REPORTED APPROXIMATELY 200 RPM PROP INDICATION FLUCTUATION IN-FLIGHT. ALL OTHER ENGINE PARAMETERS WERE OK. SYSTEM INSPECTED AND A PIN IN THE PROP MAGNETIC PICK UP CANNON PLUG WAS FOUND WITH A BROKEN WIRE. WIRE/PIN CONNECTION REPAIRED AND RUN-UP CARRIED OUT SERVICEABLE. (X)