As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
CLIMBING OUT OF GJT THROUGH 16,000 EXPERIENCED A TORQUE DROP FLUCTUATION ON LEFT ENGINE TO 30 PERCENT. EXPERIENCED CONTINUED TORQUE FLUCTUATIONS IN CLIMB THROUGH 19,000. RESET LEFT ENGINE EEC WITH NO CHANGE. RETURNED FOR PRECAUTIONARY LANDING WITH CONTINUED TORQUE DROPS ON LEFT ENGINE. REPLACED LEFT ENGINE WIRING HARNESS. PERFORMED EXTENSIVE ENGINE RUNS IAW MM 71-00-00. OPS CHECK GOOD. NO DEFECTS NOTED.