As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIR TURNBACK DUE TO OIL SMELL AND HAZE BUILD UP IN AFT CABIN AFTER TAKEOFF. GASPER AND RECIRCULATING FAN TURNED OFF, HAZE DISAPPEARED AFTER LANDING. REMOVED AND REPLACED RT WATER SEPARATOR COALESCER BAG, SERVICED RT AIR CYCLE MACHINE TO PROPER LEVEL PER MM.