As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIRCRAFT WAS GROUNDED: PILOT REPORTS OILY, DIRTY SOCK SMELL THROUGH OUT CABIN AND COCKPIT WHILE APU BLEED IS ON. MAINTENANCE FOUND OIL LEAK AT THE APU OIL COOLER. MAINTENANCE REMOVED AND REPLACED APU IAW JOB CARD 26L31049003. OPS CHECK AND LEAK CHECK GOOD.