As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
(CAN) DURING ENGINE POWER CHECK, IT WAS NOTED THAT BOTH N2 AND NR SPEEDS DROPPED BELOW NORMAL. ENGINE ALSO OVERSPEED ABOVE NORMAL WHILE LOWERING COLLECTIVE. GOVERNOR REMOVED AND LOOSE SPLINES WERE FOUND WHERE ENGAGING INTO ENGINE GEARBOX. SOME SPLINE PARTS WERE LATER FOUND IN THIS AREA.