What was found
BURNING RUBBER ODOR IN FLIGHT DECK AND CABIN FOR APPROX 30 SECONDS. ODOR DISSIPATED, FLT CONTINUED TO DESTINATION. NO EMERGENCY DECLARED. RAN ENGINE AT TAKEOFF POWER SEVERAL TIMES, ISOLATED FAINT ODOR TO LEFT PACK SYSTEM FOUND LT PACK VALVE INTERMITTENT NOT OPENING FULLY. REMOVED AND REPLACED FLOW CONTROL AND SHUTOFF VALVE PER AMM 21-51. LEAK AND OPS CHECKED GOOD. NO ODOR NOTED, REF MSU C07172247 FOLLOW UP MAINTENANCE.