What was found
MCI- UNSCHEDULED LANDING - FLT 77 - ON CLIMBOUT FROM BOS EN ROUTE TO PHX ECAM MESSAGE FOR FUEL AUTO FEED FAULT APPEARED, CREW DESELECTED AUTO AND MONITORED THE FUEL PAGE. ALL FUEL WAS BEING USED FROM LT MAIN TANK WITH X-FEED CLOSED. WITH LEFT PUMPS OFF FUEL WAS STILL BEING USED FROM LEFT SIDE. WITH LEFT AND CENTER PUMPS OFF FUEL WAS BEING USED FROM RIGHT TANK. ONCE FUEL WAS BALANCED FUEL STARTED FEEDING FROM THE LEFT TANK AGAIN, THE AIRCRAFT DIVERTED TO MCI. IN MCI MAINTENANCE TROUBLESHOT AND FOUND OVER PRESSURE PROTECTOR 96QM RUPTURED. REPLACED SAME, OPERATIONAL AND LEAK CHECKED PER AMM 28-12-4-1, ALL CHECKS WERE GOOD.