What was found
TROUBLESHOOT FOR FA & PAX IN LAST ROW, BOTH REPORTED SMELLING A STRONG OIL OR FUEL TYPE ODOR IN FLT, & THE PERIOD IMMEDIATELY AFTER ENG SHUTDOWN. NO SUCH ODOR OBSERVED IN FLIGHT DECK, OR IN CABIN AFTER DEPLANING. VERIFIED WITH CAPTAIN THAT APU WAS NOT USED AS BLEED SOUCRCE DURING ANY POINT OF FLT LEG WHILE IN AIR, CAPTAIN STATED THE PASSENGER NOTICED THE ODOR WAS WORSE IN FLT. ATTEMPTED TO FIND SOURCE OF ODOR, ISOLATING ENGS AS BLEED SOURCE AT TAKEOFF & CRUISE SPEEDS, USING BOTH PACKS AT SEPERATE TIMES FOR SINGLE PACK OPS & RAN BOTH ENGS AS BLEED SOURCE WHILE ISOLATING PACKS & THEN UNDER DUAL PACK OPS. RAN PACKS WITH APU AS BLEED SOURCE, TO SEE IF ANY DIFFERENCE. NOT ONCE AN ABNORMAL OIL OR FUEL ODOR REPORTED BY MECH IN BACK OF CABIN, AT ALL THE VARIOUS BLEED & PACK CONFIG. NO ODOR NOTED DURING ENG SHUTDOWN. NOT ABLE TO DUPLICATE ODOR. ALL ENG & PACK OPS PERFORMED IAW AMM 71-00-00, & AMM 21-51-00.