As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIRCRAFT WAS GNDED. DURING CLIMB SLIGHT SMELL & HAZE NOTICED. RECIRCULATION FAN & ENG HEAT TURNED OFF. SMELL & HAZE DISSIPATED. AT TOP OF DESCENT RECIRCULATION FAN TURNED BACK ON & SMELL REOCCURRED. FOUND BAD SEAL ON APU OIL CAP. R & R SEAL & ACCOMPLISHED PACK BURN IAW MCM 21-96-01, MCM 21-92-12, & AMM 21-20-02. GND OPERATIONAL CHECKED GOOD.