As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING BOARDING, A BURNING OIL ODOR AND HAZE WAS NOTICED WHEN TURNING ON BOTH PACKS OFF APU AIR. FOUND APU INLET CONTAMINATED WITH TURBINE OIL. REPLACED APU OIL TANK SERVICE CAP. CLEANED APU INLET AND PERFORMED PNEUMATIC DUCT BURNOUT PROCEDURE. NO FURTHER SMOKE/FUMES FOUND. (LP# 9612796)