As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
PILOT APPLIED POWER TO TAKEOFF. WHEN ACFT WAS ''LIGHT ON THE SKIDS'', PILOT OBSERVED THE NR 2 TORQUE NEEDLE ADVANCE TO 90 PERCENT. THE NR 1 TORQUE NEEDLE DECREASED ACCORDINGLY. THE NR 2 N2 NEEDLE INDICATED 106 PERCENT. PILOT REDUCED POWER INPUT AND SETTLED AIRCRAFT BACK ON LANDING GEAR. PILOT PERFORMED ENGINE SHUT DOWN. ENGINE OSCILLATED WHILE AT FLIGHT IDLE. WHEN POWER LEVER RETURNED TO GROUND IDLE, OSCILLATIONS CEASED. (X)