As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
FLT NR 466 - PBI-IAD - CREW EXPERIENCED AN 400 LB FUEL IMBALANCE FROM RIGHT WING TO LEFT. AIRCRAFT LANDED IN IAD WITHOUT INCIDENT. IAD MAINTENANCE FILLED AIRCRAFT FULL OF FUEL AND RAN ALL PUMPS. NEXT, TAXIED AIRCRAFT USING BRAKES AND THROTTLE ABRUPTLY, NO LOSS OF FUEL. COULD NOT DUPLICATE.