As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
FLT#1178, LAS-BOS. ODOR EVENT BELOW 4000' CLOSED X-BLEED AND TURNED PACK 1OFF ODOR DISSIPATED. AT GATE W/APU BLEED ON OPENED X-BLEED & TURNED PACK 1 BACK TO ON. ODOR RETURNED; REF W/O 1427101 (PERFORMED DECON LEVEL B REF AMM 21-010-00-615-803-A. NO ODOR DETECTED) NR-1 FOR RESOLUTION.