difficult to start after refueling

There is a problem within the EVAP (evaporative emissions system) that is allowing raw fuel / vapor to be drawn into the engine upon restart after re-fueling which is causing flooding.. Until repair > Holding accelerator pedal to floor while cranking will help clear flood. Diagnosis will include scan testing along with subsequent *hands-on* testing so the actual culprit can be discovered .. Likely the purge valve / solenoid.