What was found
AIRCRAFT RETURNED TO FIELD, DUE TO ERRATIC TORQUE AND EGT FLUCTUATION ON LEFT ENGINE. THE BRIDGES WERE SWAPPED ON THE TORQUE SIGNAL AND CONDITIONER. THE SIGNAL CONDITIONER WAS ADJUSTED. A FUNCTIONAL CHECK OF THE SYSTEM WAS PERFORMED WITH ALL INDICATIONS NORMAL. THE TORQUE SIGNAL CONDITIONER WAS REPLACED AFTER ARRIVING AT MAINTENANCE BASE. THE NEW UNIT WAS ADJUSTED. A FUNCTIONAL CHECK WAS PERFORMED WITH ALL INDICATIONS NORMAL. (M)