As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
(CAN) 15 MINUTES INTO FLIGHT THERE WAS NO POWER RESPONSE FROM THE LEFT HAND THROTTLE (#1 ENGINE). AIRCRAFT RETURNED TO POINT OF DEPARTURE. POST FLIGHT INSPECTION FOUND #1 ENGINE FUEL CONTROL UNIT FAULTY. FCU REPLACED. GROUND RUN CARRIED OUT AND CHECKED SERVICEABLE.