As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
THE CREW RETURNED TO THE FIELD BECAUSE THEY SMELLED SMOKE COMING FROM THE PACKS DUE TO THE APU OIL SPRAYED IN THE APU COMPARTMENT AND THE PACKS. MX RAN ENGINES AND PACKS AT A HIGH TEMP TO DISIPATE THE OIL. OP CHECKS GOOD. NO PARTS USED.