Fuel Pressure: Testing and Inspection

Fuel System Pressure Test





WARNING: Do not smoke, carry lighted tobacco or have an open flame of any type when working on or near any fuel-related component. Highly flammable mixtures are always present and may be ignited. Failure to follow these instructions may result in serious personal injury.

WARNING: Before working on or disconnecting any of the fuel tubes or fuel system components, relieve the fuel system pressure to prevent accidental spraying of fuel. Fuel in the fuel system remains under high pressure, even when the engine is not running. Failure to follow this instruction may result in serious personal injury.

WARNING: Do not carry personal electronic devices such as cell phones, pagers or audio equipment of any type when working on or near any fuel-related component. Highly flammable mixtures are always present and may be ignited. Failure to follow these instructions may result in serious personal injury.

WARNING: When handling fuel, always observe fuel handling precautions and be prepared in the event of fuel spillage. Spilled fuel may be ignited by hot vehicle components or other ignition sources. Failure to follow these instructions may result in serious personal injury.

5.4L (3V) engine

1. Remove the air intake resonator assembly bolt and loosen the clamp. Rotate the resonator upward until it stops.
- To install, tighten to 10 Nm (89 lb-in).





4.6L (3V) engine

2. Remove the Evaporative Emission (EVAP) purge valve bracket bolt and position the bracket aside.
- To install, tighten to 10 Nm (89 lb-in).





All engines

3. NOTE: 4.6L (2V) shown, 4.6L (3V) and 5.4L (3V) similar.

Remove the fuel pressure relief valve cap.





4. NOTE: 4.6L (2V) shown, 4.6L (3V) and 5.4L (3V) similar.

Install the Fuel Pressure Test Kit onto the fuel pressure relief valve.





5. NOTE: It may take more than one key cycle to pressurize the fuel system.

Cycle the ignition key to the on position and wait 3 seconds to pressurize the fuel system. Check for leaks before starting the engine.

6. Test the fuel system pressure to make sure it is within the specified range. For additional information, refer to Specifications.

7. NOTE: 4.6L (2V) shown, 4.6L (3V) and 5.4L (3V) similar.

NOTE: Open the drain valve slowly to relieve the fuel system pressure. This may drain fuel from the system. Place the fuel in a suitable container.

Upon completion of the fuel system pressure test, open the drain valve on the Fuel Pressure Test Kit and relieve the fuel system pressure.





8. NOTE: 4.6L (2V) shown, 4.6L (3V) and 5.4L (3V) similar.

Install the pressure relief valve cap.

- Tighten to 6 Nm (53 lb-in).





5.4L (3V) engine

9. Loosen the clamp and rotate the air intake resonator assembly into position and install the bolt.
- Tighten to 10 Nm (89 lb-in).





4.6L (3V) engine

10. Position the EVAP purge valve into place and install the bracket bolt.
- Tighten to 10 Nm (89 lb-in).





All engines

11. NOTE: It may take more than one key cycle to pressurize the fuel system.

Cycle the ignition key to the ON position and wait 3 seconds to pressurize the fuel system. Check for leaks before starting the engine.