Custom Cruiser RWD V8-350 5.7L (1992)
Fuel System Schematic
TEST DESCRIPTION: The numbers below refer to circled numbers on the diagnostic chart.
1.
Fuel pressure present, but less than 62.0 kPa (9.0 psi) may cause the following:
^
Amount of fuel to injectors OK, but pressure is low, less than 62.0 kPa (9.0 psi). System will be running lean and may set a Code 44. Also,
hard starting cold and poor overall performance may result.
^
Restricted flow causing pressure drop. Normally, a vehicle with a fuel pressure of less than 62.0 kPa (9.0 psi) at idle will not be driveable.
However, if the pressure drop occurs only while driving, the engine will normally surge then stop as pressure begins to drop rapidly.
2.
Turning the fuel pump "ON" and restricting the fuel flow at the fuel pressure gage as shown will determine if the fuel pump can supply enough
fuel pressure at the injector in order to operate properly above 62.0 kPa (9.0 psi).
NOTE: DO NOT restrict the fuel return line. This may damage the fuel pressure regulator.
3.
This test determines if the high fuel pressure problem is due to a restricted fuel return line or a throttle body pressure regulator. Apply battery
voltage to the fuel pump test connector only long enough to get an accurate fuel pressure reading.
