Fuel Pressure: Testing and Inspection

Fuel Pressure Test:

WARNING: FUEL system pressure must be released before a fuel system hose or component is disconnected.

1. Fuel system pressure must be released each time a fuel hose is to be disconnected. Release fuel system pressure.
2. Remove protective cover from service valve on the fuel rail.
3. Connect Fuel Pressure Gauge C-4799 to fuel rail service valve.

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

4. Place the ignition key in the ON position. Using the scan tool, access actuator test "Fuel System Test." The Fuel System Test will activate the fuel pump and pressurize the system.
- Standard value: 330-350 kPa (47-50 psi)

NOTE: The specifications listed are determined without vacuum applied to the fuel pressure regulator.

5. Use the scan tool "Fuel System Test" to pressurize the system. Ensure fuel does not leak from the fuel rail service valve.









6. If pressure is not correct, troubleshoot and repair according to the tables.
7. Using the scan tool, with the ignition key in the ON position, repeat the "Fuel System Test."
8. Turn the ignition switch off and observe fuel pressure gauge reading. Normal if the reading does not drop within 2 minutes. If it does, observe the rate of drop and troubleshoot and repair according to the table below.
9. Remove fuel pressure gauge and reinstall protective cover onto fuel rail service valve.