As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
BOI-SUP-ON FLIGHT NUMBER 2424, BURNING OIL SMELL DETECTED DURING CLIMB. OIL SMELL DISSIPATED AFTER APU SHUTDOWN. VISUALLY INSPECTED APU EXHUAST & INTAKE. NO DEFECTS NOTED. GROUND RAN APU. SLIGHT OIL SMELL WHEN FIRST STARTED. REMOVED ND REPLACED APU. OPERATIONAL TEST GOOD. AIRCRAFT RETURNED TO SERVICE.