As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
STRONG ODOR REPORTED ON INBOUND FLIGHT AND AGAIN AT GATE DURING BOARDING. MAINTENANCE FOUND OIL LEAKING INTO APU PLENUM ASSEMBLY AT CASE SPLIT SEAL AND SEVERAL EXTERNAL LEAKS. REMOVED AND REPLACED THE APU. CONFIRMED LEAK AT GEARBOX LIP SEAL.