As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ORD FLT 5843 THE CREW REPORTED FUEL SMELL IN THE COCKPIT AFTER APU START WITH PACK RUNNING ON ENGINE BLEED. MAINTENANCE INSPECTED AND PERFORMED ENGINE RUNS WITH BLEEDS ON. FOUND NO FUEL SMELL COMING FROM THE PACKS. THE AIRCRAFT WAS RELEASED FOR SERVICE.