What was found
DURING ALL PHASES OF FLIGHT (FLT 1665, CLT-STL), CREW REPORTED THE AIR HAD A MUSTY/OILY ODOR. SWITCHED PACKS OFF ALTERNATELY - AIR SEEMED TO IMPROVE WITH PACK 2 OFF. FLIGHT CONTINUED ONTO DESTINATION TO STL. MAINTENANCE PLACED THE APU ON MEL 49-10-01A. SUBSEQUENTLY, THE NEXT FLIGHT (FLT 1053, STL-CLT) THE FOLLOWING MORNING, THE CREW REPORTED A MUSTY/OILY ODOR EMITTING FROM VENTS DURING ALL PHASES OF FLIGHT. FLIGHT CONTINUED ONTO DESTINATION TO CLT. MAINTENANCE REMOVED AND REPLACED THE APU PER J/C 26L31049003. LEAK AND OPS TEST OK. ACCOMPLISHED J/C 26L00021001 - T/S CABIN AIR QUALITY, J/C 26L00021002 - APU SMELL IN CABIN AND J/C 26L00021004 - DECONTAMINATION OF THE ECS A319/A320/A321 (ENGINES AND APU). CLEARED MEL 49-10-01A.