What was found
DURING CLIMB-OUT FROM BTV, THE A/C EXPERIENCED CONTINUOUS YAW FLUCTUATIONS. TORQUE, ITT, FUEL FLOW, AND PROP RPM ALSO FLUCTUATED FOR THE NR 2 ENGINE. A/C RETURNED TO FIELD AND LANDED WITHOUT INCIDENT. MAINTENANCE T/S SYSTEM, FOUND NR 2 ENGINE ECU AT FAULT PERFORMED SATISFACTORY TEST FLIGHT WITH NR 2 ECU INOP PER MEL PROCEDURES. SUBSEQUENT MTC RON, MAINTENANCE REMOVED AND REPLACED THE NR 2 ENGINE WIRING HARNESS. A/C RETURNED TO SERVICE. (M)