As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
PDX - DURING TROUBLE SHOOTING OF APU DISCREPANCY, MAINTENENCE PERSONEL NOTED THE SMELL OF OIL IN THE CABIN. INSPECTED BLEED AIR DUCTING. NO OIL CONTAMINATION NOTED. REMOVED AND REPLACE APU. OPERATIONAL CHECKS GOOD. AIRCRAFT RETURNED TO SERVICE.