A PC12 engine failed to respond during a level off after a descent. Subsequent trouble shooting caused a very high ITT at which time the engine was shut down; an emergency declared and the flight diverted to a nearby airport.

Narrative

In the descent to 12;000 FT we reduced power to 4-5 PSI to slow to 170 KIAS. Approaching 12;000 FT MSL we added power and there was no engine response to PCL (Power Control Lever) movement. We noticed torque at 0.0 and Ng at 47%; but we didn't notice what the fuel flow at that time. I pushed the nose over to maintain 115-120 KIAS best glide speed and I went through the memory items for engine failure by moving the PCL forward with no response then went to idle and moved the MOR (Manual Over Ride) up slowly to see if the engine would respond. We felt the engine vibrate and the ITT (Inter-Turbine Temperature) climbed rapidly to 934 degrees C and I immediately retarded the MOR to the stowed position. At this time we went into IMC conditions between 12;000 FT to 11;000 FT MSL; declared an emergency with ATC at 11;400 FT MSL and started to go through the engine failure checklist and shut the engine down by going to cutoff/feather. We coordinated with ATC to get directions to the closest suitable airfield and we put it in the GPS and determined that it was 15 NM to our north. We executed a 180 degree turn at 10;000 FT MSL; continued our descent towards the airport and broke out of the clouds at approximately 5;500 FT MSL 4 NM south of the airport. We set up for a left downwind for runway; lowered the flaps to 15 degrees on downwind to base; lowered landing gear handle and putting the non-essential switch to override on base to final; then went to 30 degrees of flaps on final when landing was assured. Landing was uneventful. We believe the engine failure was due to a malfunctioning fuel control unit. Recommend keeping a constant eye on the torque and Ng while in a low power descent.