Fuel Pressure: Testing and Inspection
FUEL PRESSURE TESTWARNING: FUEL SYSTEM PRESSURE MUST BE RELEASED BEFORE A FUEL SYSTEM HOSE OR COMPONENT IS DISCONNECTED.
The specifications listed in the Fuel System Pressure Chart are determined without vacuum applied to the fuel pressure regulator.
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 MB995051 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 Oft 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)
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 table below.
7. Using the scan tool, with the ignition key in the ON position, repeat the "Fuel System Test".
8. Turn the ignition switch oft and observe fuel pressure gauge reading Normal it the reading does not drop within 2 minutes. If it does, observe the rate of drop and troubleshoot and repair according to the table.
9. Remove fuel pressure gauge and reinstall protective cover onto fuel rail service valve.