As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
RETURNING TO THE GATE, ODOR IN CABIN DURING TAXI. R & R THE NR 1 ENGINE IAW AMM 71-00-00-400-801-A & 71-00-00-400-802-A. PERFORMED 5 POINT CALIBRATION RUN ON THE NR 1 ENGINE, NO DISCREPANCIES NOTED. ALL WORK WAS PERFORMED IAW MM 72-00-00.