FUEL DELIVERY SYSTEM - V8 (Operation): DESCRIPTION AND OPERATION

FUEL DELIVERY SYSTEM - V8

19-2-10 DESCRIPTION AND OPERATION

Operation
When the ignition switch is moved to position II, the fuel pump relay in the engine compartment fusebox is energised 
by the ECM. Battery voltage is supplied from the fuel pump relay to the fuel pump which operates. If engine cranking 
is not detected by the ECU within a thirty second period, the ECU will 'time-out', de-energising the fuel pump relay.
 

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 ENGINE MANAGEMENT SYSTEM - V8, DESCRIPTION AND OPERATION, Description - engine 

management.

The fuel pump draws fuel from the swirl pot and pumps it along the fuel feed pipe to the injector fuel rail on the engine. 
When the pressure in the fuel feed line reaches 3.5 bar (50 lbf.in

2

) the fuel pressure regulator opens and relieves 

pressure by directing fuel back into the swirl pot. The pressure regulator is constantly opening and closing to maintain 
the pressure in the fuel feed pipe and the fuel rail at 3.5 bar (50 lbf.in

2

).

The pressure is felt at each of the eight injectors connected to the fuel rail. The ECM controls the injection timing and 
energises each injector to allow a metered amount of fuel at pump pressure to be injected into the inlet tract of the 
inlet manifold. The atomised fuel from the injector is mixed with air from the inlet manifold before passing into the 
cylinder.