Fuel Pressure: Testing and Inspection

Fig. 3 Checking Fuel Pressure At Intake Manifold:

NOTE: The fuel system operates at approximately 338 kPa (48 psi). Check fuel system pressure at the test port on the fuel rail Fig. 1.

1. Remove cap from fuel pressure test port on fuel rail.
2. Connect Fuel Pressure Gauge C-4799B to test port Fig. 3.

CAUTION: When using the ASD Fuel System Test, the ASD relay and fuel pump relay remain energized for 7 minutes or until the test is stopped, or until the ignition switch is turned to the OFF position.

3. Place ignition key in the ON position. Using DRB Scan Tool, access ASD Fuel System Test. The ASD Fuel System Test will activate the fuel pump and pressurize the system.
- If the gauge reading equals 338 kPa (48 psi) further testing is not required. if pressure is not correct, record the pressure.
- If pressure is above specifications, check for a kinked or restricted fuel return tube (from filter to pump module).
- If the fuel return tube is not pinched or restricted, replace the fuel pressure regulator.
- If fuel pressure is below specifications, refer to the diagnosis chart for Fuel Pressure Below Specifications below.

Fuel Pressure Below Specifications Chart:

* Pressure gauge should rise rapidly. If pressure rises slowly, inlet strainer is plugged enough to cause drive ability problem.

4. Replace Pressure Test Port Cap when finished doing pressure test.