What was found
DESCENDING OUT OF CRUISE ALTITUDE, RT THROTTLE LEVER HAD NO EFFECT ON ENGINE POWER SETTING. RT ENGINE MAINTAINED CRUISE POWER, EVEN WHEN RT THROTTLE WAS BROUGHT TO IDLE. CREW SECURED RT ENGINE AS N2 WAS GOING TO EXCEED TOLERANCE, DECLARED AN EMERGENCY, & LANDED UNEVENTFULLY. PERFORMED A FCU CONTAMINATION CHECK IAW MM 73-20-01, NO DEFECTS NOTED. REPLACED FILTER IAW MM 73-20-01. R & R FCU WITH AN OVERHAULED UNIT, OPS & LEAK CHECKED GOOD IAW MM 71-00-00.