Fuel Pressure Release: Service and Repair

WARNING: Do not smoke, carry lighted tobacco or open flame of any type when working on or near any fuel related component. Highly flammable mixtures are always present and may be ignited, resulting in possible personal injury.

CAUTION: Fuel supply lines will remain pressurized for long periods of time after engine shut down. This pressure must be relieved before servicing of the fuel system is begun. A valve is provided on the throttle body for this purpose. Remove the air cleaner and relieve system pressure by using Rotunda pressure gauge tool T80L-9974-A or equivalent and drain the system through the drain tube.

On CFI engines, a valve is provided on the throttle body for this purpose. This valve can be located by removing the air cleaner. On turbocharged EFI engines this valve is located in the flexible fuel supply tube approximately 305mm (12-inches) back from where it connects to the engine fuel rail.

To relieve fuel system pressure on CFI engines, use Rotunda Pressure Gauge Tool T8OL-9974-A or equivalent and drain the system through the drain tube.

Electronic fuel injected engines are equipped with a pressure relief valve in the fuel supply line in the engine compartment.

The pressure relief valve on EFI engines is located in the engine compartment on the fuel supply line except on certain vehicles. On other vehicles the valve is located on the driver's side of the engine compartment in the flexible hose assembly which connects to the fuel rail on the engine.

Before opening the fuel system on vehicles with EFI engines, relieve fuel pressure as follows:

1. Remove fuel tank cap.
2. Disconnect vacuum hose from fuel pressure regulator located on the engine fuel rail.






3. Using a hand vacuum pump, apply about 84.2 kPa (25 in. Hg) pressure to the pressure regulator.

NOTE: Fuel pressure will be released into the fuel tank through the fuel return hose.