DeVille DHS V8-4.6L VIN Y (2000)
Fuel Pressure: Testing and Inspection
Fuel System Pressure Test
CIRCUIT DESCRIPTION
Schematic
When the ignition switch is turned ON, the Powertrain Control Module (PCM)will turn ON the in tank fuel pump. The in-tank fuel pump will remain
ON as long as the engine is cranking or running and the PCM is receiving reference pulses. It there are no reference pulses, the PCM will turn the
in-tank fuel pump OFF 2 seconds after the ignition switch is turned ON or 2 seconds after the engine stops running.
The in-tank fuel pump is an electric pump attached to the fuel sender assembly. The in-tank fuel pump supplies fuel through the fuel flex pipe through
the fuel feed output fitting on the molded cover. The fuel then goes to the fuel feed pipe from the through an in-line fuel filter to the fuel rail assembly.
The fuel pump is designed to provide fuel at a pressure above the pressure needed by the fuel injectors. A fuel pressure regulator, attached to the fuel
rail, keeps the fuel available to the fuel injectors at a regulated pressure. Unused fuel is returned to the fuel tank by a separate fuel return pipe. The fuel
pressure gauge J 34730-1A and fuel pipe shut-off adapters J 37287 are use for fuel system diagnosis. The fuel pressure gauge connects to the fuel
pressure connection.
TEST DESCRIPTION
