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: 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.

1. NOTE: 6.8L shown, 4.6L and 5.4L similar.

Remove the cap from the fuel pressure relief valve located on the fuel rail.






2. NOTE: 6.8L shown, 4.6L and 5.4L similar.

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






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

4. 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.

NOTE: 6.8L shown, 4.6L and 5.4L similar.

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






5. NOTE: 6.8L shown, 4.6L and 5.4L similar.

Install the cap on the fuel pressure relief valve.






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

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