What was found
AIRCRAFT WAS GROUNDED: DESCENDING THROUGH 10000 FT STRONG SWEET ODOR BECAME PREVALENT IN THE FLIGHT DECK. JUST AFTER LANDING FLIGHT ATTENDANTS NOTIFIED US OF STRONG GYM SOCK SMELL BETWEEN DOOR 3 AND DOOR 4. CABIN FANS WERE TURNED OFF AND SMELL SUBSIDED SLIGHTLY. APU WAS OFF. MAINTENANCE FOUND THE APU FUEL CONTROL UNIT (FCU) LEAKING AND REPLACED IT PER AMM 49-32-11. MAINTENANCE ALSO FOUND THE APU OIL COOLER TUBE CLOGGED AND CLEANED IT PER AMM 49-26-55 (AALA202411139033). MAINTENANCE ALSO CLEANED THE APU GEARBOX VENT LINE PER AMM 49-26-55 (AALA202411133852). A DECONTAMIANTION OF THE ENVIRONMENTAL CONTROL SYSTEM WAS ACCOMPLISHED PER TASK CARD 26L00021014. A SATISFACTORY LEAK / OPERATIONAL CHECK WAS ACCOMPLISHED.