See Figures 1, 2 and 3
- Disconnect the negative battery cable.
- Remove the fuel tank filler cap to release any fuel tank pressure.
- Unscrew the plastic cap from the pressure test port on the fuel rail. On the 8.0L engine, the test port is found at the front of the engine.
- Obtain a fuel pressure gauge/hose from a fuel pressure gauge tool set No. 5069, or equivalent. Remove the gauge, then place the gauge end of the hose into a suitable gasoline container.
- Place a shop towel under the test port.
- Screw the other end of the hose onto the fuel pressure port to relieve the pressure.
- When the pressure has been relieved, remove the hose and cap the port.