The Pontiac Grand Prix is a purely American car, from its driver-friendly cockpit to its sedan styled body. And the newer Grand Prix has been updated with such handy technologies as keyless entry and OnStar service. Despite the recent additions, the 2002 and more recent Grand Prix models still allow for seamless fuel tank installation.
Turn off the negative battery terminal on the car's battery. Remove the fuel tank filler cap and insert a siphoning hose to empty the remaining fuel into a gas container.
Disconnect all fuel lines and hoses on and around the fuel tank. Use a screwdriver to remove the tank shield, and remove the tank straps around the tank. Lower the tank to the ground with a floor jack.
Lift the new fuel tank up under the Grand Prix's trunk with a floor jack. Connect the fuel pump/gauge sending unit wires back to the fuel tank. Attach the fuel pump ground strap to hold the sending unit in place.
Connect both fuel tank retaining straps to keep the fuel tank close the car's body. Re-install the fuel tank shield at the top of the fuel tank, securing it with plastic pushpins at each end of the shield. Make sure the pushpins are tightly in before going any further.
Install the exhaust pipe to the left of the rear right wheel. Attach the fuel feed, the vapor return line and the filler neck hose to the top of the fuel tank. Connect the vent tubes to the top rear of the fuel tank with the other wires and hoses. Plug in the electrical connector for the fuel pump and the fuel gauge sending unit at the front of the fuel tank to activate it.
Empty the fuel from the gas container into your fuel tank's drain. Then, cover the fuel tank with the fuel tank filler cap to restore fuel pressure to your Grand Prix. Activate your car's battery by plugging in the negative battery terminal cable.
Check your car for any loose wiring or leaks. If there are no leaks, start your Pontiac and let it run for a few minutes. Take your car for a short drive to test your engine to make sure it's running smoothly.
