What was found
PARTIAL LOSS OF POWER IN CRUISE FLT 2500 MSL ON LEFT TANK. LOSS OF FUEL PRESSURE, SWITCHED TANKS, ENGAGED AUX FUEL PUMP AND REGAINED POWER. MONITORED ENGINE GAUGES, APROX 15 GAL OF 100 LL IN TANK. LANDED ON MECHANICAL PUMP. NO ISSUES ON LANDING. NOTIFIED DIRECTOR OF MAINTENANCE AND DIRECTOR OF OPERATIONS. NOTIFIED FSDO. MAINTENANCE TROUBLE SHOOTING SYMPTOMS FOUND NO ISSUE AFTER INITIAL POWER LOSS. LOST POWER IN FLIGHT, SWITCHED TANKS WITH PROPELLER WINDMILLING. ENGINE RESTARTED AND TURNED OFF AUX PUMP. LANDED AT HOME BASE. ACTUAL CAUSE OF LOSS OF POWER UNK. MAINTENANCE CONTINUING TO TROUBLESHOOT FUEL TANK, FUEL SYSTEM FILTERS (MISC) AND OTHER POSSIBLE CAUSES. SENDING MECHANICAL FUEL PUMP AND FUEL CONTROL SERVO TO REPAIR STATION FOR EVALUATION.