What was found
PILOT REPORTS ERRATIC ENGINE OPERATION AT LOW POWER SETTINGS AND APPEARED TO BE 'MISFIRING' ON FINAL. MAINTENANCE PERSONNEL RAN ENGINE AND NOTICED AT ANY RPM BELOW 1,500, ENGINE WOULD 'LOPE' AND WAS ACCOMPANIED BY ERRATIC FUEL FLOW INDICATIONS. FUEL SERVO WAS REPLACED BY AN OVERHAULUED UNIT, S/N 36542.