As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ACFT SMELLS OF VAPOR & BURNING OIL WITH APU & ENG BLEED. REPLACED RECIRCULATION FILTERS IAW 21-25-02/401. RAN APU AND BOTH ENGINES ONE AT A TIME. THE ODOR WAS ONLY NOTICEABLE WHEN USING THE APU BLEED. ENINE RUNS WERE NORMAL. SUGGEST PLACING APU BLEED ON MEL.