As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
WHEN APU BLEED ON & PACKS ON, A VERY STRONG DIRTY SOCK ODOR WAS NOTICED INSIDE AIRCRAFT. INITIALLY ODOR WAS ONLY SLIGHT AND CONTINUED TO INTENSIFY. FOUND APU LEAKING OIL FROM BOLTS OF FIRST FLANGE OF GAS GENERATOR MIGRATING ALONG PLENUM FLANGE AND INGESTING THROUGH CRACKS IN LEFT FORWARD CORNER OF PLENUM FLANGE. REMOVED AND REPLACED APU. OPS CHECKED GOOD. VENDOR HONEYWELL CONFIRMED REASON FOR REMOVAL. FOUND OIL AT TURBINE CASE SPLIT LINE, COOLING FAN AND INLET.