What was found
MIA - FLT 2104 - EN ROUTE BZE-MIA, FUEL QTY GAUGE FOR NR 2 TANK FLUCTUATED AND INDICATED A DECREASING FUEL SUPPLY AT AT GREATER RATE THAN FUEL USAGE FROM TANKS 1 AND 3. AN EMERGENCY WAS DECLARED AND AIRCRAFT LANDED MIA WITHOUT INCIDENT. NR 2 FUEL TANK AND SUPPLY LINES INSPECTED FOR LEAKS. NONE FOUND. REPLACED NR 2 FUEL SYSTEM DIGITAL CALIBRATION TRIM UNIT. SYSTEM GROUND CHECKED NORMAL OPERATION. (M)