July 1: So it begins. Don't worry, this is not in the correct legal jurisdiction!
Fuel Fill Pipe
WARNING: This page is about a different car, the 2005 Saturn L300. However, it is still accessible from the selected car via links, so may be relevant.
Fig 1: View Of Fuel Fill Pipe
Courtesy of GENERAL MOTORS CORP.
The fuel fill pipe has a built-in restrictor in order to prevent refueling with leaded fuel.