What was found
DURING CLIMB LEFT ENGINE PROP CAME OUT OF SYNC FOLLOWED BY A LEFT SEVERE ENGINE VIBRATION (TORQUE JUMPED TO 130%). LEFT ENGINE ITT WENT INTO THE RED. POWER WAS REDUCED TO IDLE, THE TORQUE AND ITT WENT TO THE GREEN. ADVANCING THE THROTTLES WOULD CAUSE SAME RESULTS TORQUE/ITT IN THE RED. CREW DECIDED TO SHUTDOWN THE LEFT ENGINE ENGINE. FOLLOWED CHECKLIST FOR SINGLE ENGINE LANDING. EMERGENCY WAS DECLARED AND A DIVERT BACK TO KIWA WAS PERFORMED. MAINTENANCE REPLACED THE LEFT ENGINE. ENGINE RIG/PERFORMANCE RUNS PERFORMED WITH THE DEFECTS NOTED. AIRCRAFT WAS RETURNED TO SERVICE.