What was found
FLT 1018. F/A REPORTED ODOR IN CABIN ACCOMPANIED BY HAZE, POSSIBLE AIR CONTAMINATION, IN CRUISE & DESCENT. NO CONTAMINATION OR ODOR NOTICED IN COCKPIT. LANDED WITHOUT FURTHER INCIDENT. ACFT INSPECTED & RELEASED FOR A MX FLT. APPROX 2 HOURS INTO FLT, 2L LAV SMOKE DETECTOR CAME ON, ALONG WITH SLIGHT ODOR IN VICINITY OF 2L LAV. SMOKE DETECTOR WENT OUT AFTER FEW MINUTES, & SMOKE CLEARED. REPEATED 3 TO 4 TIMES. TURNED OFF LT PACK & RT PACK FOR AWHILE. NO AFFECT ON SMOKY ODOR. FLT CONTINUED & LANDED WITHOUT FURTHER INCIDENT. FOUND APU OIL COOLING FAN PLENUM TO HAVE DAMAGE. PERFORMED REMOVAL OF OIL CONTAMINATION FROM THE AC & PNEUMATIC SYS TASK, USING BOTH ENGINES & HUFFER. REPLACED APU COOLING FAN ASSY.