What was found
AT ROTATION, RECEIVED AN FMC MESSAGE EICAS ADVISORY AND INSUFFICIENT FUEL ON MCDU. NOTICED TOTALIZER ROLLING BACK FROM 22K DOWN TO 16K PASSING 400FT AGL. DECLARED AN EMERGENCY AND LANDED. INSPECTED, AND FOUND NO EVIDENCE OF FUEL LEAK, STUCK TANK AND READINGS OF LT STICK2 30 AND RT STICK 2 31 WHICH MATCHES THE FUEL QUANTITY INDICATOR OF LT TANK 10K AND RT TANK OF 9.7K. PERFORMED A BITE TEST OF FQPU IAW TSM 28-41, TREE 847, NO DEFECTS RECORDED. CANNOT DUPLICATE ISSUE. REMOVED AND REPLACED FQPU IAW AMM 28-41-08-4. BITE TESTED OK.