What was found
(CAN) ENGINE PWR LOST WITH N2/NR SPEED DECELERATING TO ABOUT 90 PERCENT DURING LEVEL CRUISE FLIGHT AT 2000 FT. PILOT PROCEEDED TO EXECUTE SUCCESSFUL EMERGENCY LANDING. MX INSPECTED THE FUEL SYS FINDING NO APPARENT FAULT. A GROUND RUN WAS PERFORMED SATISFACTORILY. AS A PRECAUTION, FCU, PT GOVERNOR AND FUEL NOZZLE WERE REPLACED. ACFT RETURNED TO SERVICE. FURTHER INVESTIGATION IN O/H SHOP CONCLUDED THAT THE MOST PROBABLE CAUSE OF THE DECELERATION WAS CONTAMINANTS DISLODGED FROM THE PT GOVERNOR OVERSPEED BLEED ORIFICE AND MOMENTARILY TRAPPED BETWEEN THE O/S LEVER AND THE ORIFICE SEAT, BLEEDING OFF "PY" DIRECTLY FROM THE FCU, FOR WHICH THE GOVERNING SECTION OF THE PT GOVERNOR COULD NOT TOTALLY COMPENSATE FOR. THE PT GOVERNOR TSO=1673.1 HRS