As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
SOUR SMELLL IN THE CABIN FOUND OIL ALL THE WAY TO THE APU. DESCRIPTION OF ODOR/FUMES: TEMPORARY ODOR DURING DESCENT. APPARENT CABIN SOURCE: UNKNOWN. FLIGHT DECK. NO VISIBLE SMOKE/HAZE. NO MEDICAL ATTENTION REQUIRED.-REF TSM 05-50-00. APU VERIFIED NO LEAKS. PER CONDITIONED AC WITH APU & ENG 1&2. NO SMELL. ISOLATED PACK 1&2. NO SMELL NOTED. R&R CARTRIDGES FILTERS IAW AMM 21-61-00, 49-00-00 & 72-00-00