As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ENGINE FUEL VALVE RT EICAS & FUEL VALVE LIGHT ILLUMINATED WHEN ENG SHUTDOWN DURING TAXI HOLD. WHITE SMOKE WAS REPORTED FROM EXHAUST. CHECKED & CLEANED CONNECTOR FOR NR 2 ENGINE FUEL CONTROL UNIT. STARTED AND SHUT DOWN ENGINE 2 SEVERAL TIMES WITH NO FAULTS.