What was found
BNA - FLT 548 - ON CLIMB-OUT FROM BNA, CREW NOTED THAT THE NR 1 ENGINE POWER WAS SURGING/FLUCTUATING FROM 60 TO 98 PERCENT RANDOMLY. CREW ACCOMPLISHED CHECKLIST/SPECIAL PROCEDURES AND DISCONNECTED AUTOPILOT, AUTOTHROTTLE AND PMC WITH NO HELP. FLIGHT RETURNED TO FIELD AT BNA AND LANDED WITHOUT FURTHER INCIDENT. NO EMERGENCY DECLARED. MAINTENANCE REMOVED AND REPLACED THE NR 1 ENGINE MAIN ENGINE CONTROL (MEC) PER MM 73-21-01. ENGINE OPS CHECK GOOD. (M)