As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
WHILE EN ROUTE, FLIGHT CREW NOTICED LT RPM FLUCTUATION. ADJUSTMENT OF POWER LEVER ONLY REDUCED RPM. ENGINE POWER WAS LOST. CREW ELECTED TO DIVERT TO TYS AND AN UNEVENTFUL LANDING WAS MADE. MAINTENANCE FOUND A FUEL LEAK AT A DEFECTIVE O-RING FITTING ON THE MAIN FUEL LINE. O-RING WAS REPLACED AND THE ENGINE PERFORMANCE RUN WAS SATISFACTORY.