Fuel Pressure Release
WARNING: This page does not describe the selected car, but rather 24 other vehicles, including the 1997 Oldsmobile Bravada, 1997 GMC Sonoma, 1997 GMC Savana, 1997 GMC Safari, and 1997 GMC Pickup. However, it is still accessible from the selected car via links, so may be relevant.
Disconnect battery terminals. Loosen fuel tank cap to relieve tank pressure. Connect one end of fuel gauge hose to pressure relief fitting at rear of intake manifold. Place other end of hose in a container. Open relief valve to release pressure.