As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
HAD TO X FEED TWICE DUE TO 1500LBS IMBALANCE. FMC SHOWED EVEN BURN ON BOTH ENGINES. DUE TO HISTORY OF UNWANTED FUEL TRANSFER, REPLACE THE FWD AND AFT FUEL CROSSFEED VALVES & ACTUATORS. REPLACED BOTH XFEED VLVS AND ACTUATORS, AND ALL TESTED NORMAL.