As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIRCRAFT WAS GROUNDED: NEAR THE END OF THE START CYCLE FOR ENGINE NUMBER 1, A HEAVY FUME SMELL WAS EXPERIENCED BY THE PILOTS AND ALL FLIGHT ATTENDANTS. WE ABORTED THE ENGINE START AND THE SMELL DISSIPATED. DETERMINED SOURCE OF ODOR TO BE THE APU WHEN THE BLEED IS SELECTED ON AND VERIFIED NO FUMES WHEN APU BLEED SELECTED OFF. (OPEN).