What was found
(CAN) ON APPROACH INTO AIRPORT AND DESCENDING BELOW 10,00 FEET, AN ODOUR BEGAN TO EMANATE INTO THE COCKPIT AND CABIN. THE ODOR DISIPATED SOMEWHAT BELOW 6000 FT. AFTER ARRIVAL AT THE GATE, 4 OF THE 5 CREW MEMBERS FELT SLIGHTLY DIZZY AND SLIGHTLY OFF BALANCE. RT ENGINE CHANGE DUE OIL FOUND IN FIRST AND SECOND STAGE COMPRESSOR.