As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
(CAN) DURING TAXI-OUT, 1 ENGINE ROLLED BACK TO SUB-IDLE AND SEEMED TO HUNG. THE ENGINE WAS SHUTDOWN AND LARGE AMOUNT OF SMOKE APPEARED IN THE BACK. STREAM OF FUEL POOLED UNDER THE ENGINE. ACFT WAS TOWED BACK TO ORIGIN. GROUND TECH CONFIRMED FUEL LEAKING FROM THE ENGINE FUEL PUMP DRAIN. FUEL PUMP AND HMU ARE BEING REPLACED.