As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AFTER PACKS WERE TURNED ON ACFT HAD A FOUL SMELL. DURING PACK BURNOUT FOUND APU TO BE THE SOURCE OF OIL SMELL IN ACFT CABIN. AFTER APU SHUTDOWN, THEN RE-START SMELL CAME BACK. RECOMMEND REPLACING CABIN RECIRC FILTERS DUE TO POSSIBLE CONTAMINATION.-DURING PACK BURNOUT FOUND APU TO BE THE SOURCE OF OIL SMELL IN ACFT CABIN. AFTER APU SHUTDOWN, THEN RE-START SMELL CAME BACK. REPLACED IAW TOD.