What was found
AIRCRAFT WAS GROUNDED: IN FLIGHT THE NUMBER 2 FUEL QUANTITY INDICATION BLANKED FOR 2 TO 3 MINUTES. WHEN THE INDICATION RETURNED THE NUMBER 2 QUANTITY WAS APPROXIMATELY 400 LBS BELOW THE NUMBER 1 QUANTITY. THE FUEL HAD BEEN BALANCED SEVERAL MINUTES PRIOR TO WITHIN 100 LBS. FUEL FLOW WAS THE SAME FOR BOTH ENGINES. PERFORMED FIM 28-41-00-810-801. FQIS BITE PROCEDURE FOUND COMPENSATOR AT FAULT. REMOVED AND REPLACED THE RIGHT HAND FUEL TANK COMPENSATOR, OPERTIONAL AND LEAK CHECK GOOD. PER AMM 28-41-21-400-801.