As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIRCRAFT WAS GROUNDED: CREW REPORTED BOTH PACKS HAVE A BURNT OIL SMELL. MAINTENANCE FOUND THE APU OIL LUBE MODULE FILTER LEAKING AND REPLACED THE PACKING IN THE OIL LUBE MODULE FILTER PER AMM 49-91-41. A SATISFACTORY LEAK / OPERATIONAL CHECK WAS ACCOMPLISHED.