As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIRCRAFT WAS GROUNDED: OIL FUMES ON APPROACH TO LANDING. MAINTENANCE ACCOMPLISHED TASK CARD 26L00021001 SMOKE ODOR FUMES TROUBLE SHOOTING ALONG WITH TASK CARDS 26L260021003 AND 26L00021004 DECONTAMINATION OF ENVIRONMENTAL CONTROL SYSTEM. REPLACED BOTH HEPA FILTER AS REQUIRED PER AMM 21-21-41.