Fuel Tank Filler Neck
WARNING: This page is about a different car, the 2004 Pontiac Vibe. However, it is still accessible from the selected car via links, so may be relevant.
In order to prevent refueling with leaded fuel, the fuel filler neck has a built-in restrictor and deflector. The opening of the restrictor admits only the smaller unleaded fuel nozzle. The nozzle must be fully inserted to bypass the deflector. Any attempt at refueling with leaded fuel will result in fuel splashing out of the filler neck.