As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
CREW REPORTED STRONG FUEL SMELL IN COCKPIT AND CABIN AFTER STARTING THE APU WHILE A/C WAS ON THE GROUND. EMERGENCY VEHICLES RESPONDED AS WELL. MAINTENANCE PERFORMED OPS CHECK OF APU PER EMB AMM, AND REPORTED NO SMELLS OR DEFECTS NOTED WITH APU. A/C WAS RETURNED TO SERVICE.