System overview
The fuel system on the Saab 9-3 operates through an electric fuel pump drawing fuel from the fuel tank and building up fuel pressure in the system. The pressure level is determined by the pressure regulator, which maintains a constant fuel pressure relative to the pressure in the engine intake manifold. In this way, the amount of fuel injected is not affected by the varying pressure in the intake manifold but is determined only by the opening duration of the injectors.
Fuel is supplied to the engine through injectors (electrically controlled solenoid valves) mounted in the intake manifold close to the intake valves and coupled together via a common fuel rail.
The fuel injector opening duration is controlled by electrical impulses from the control module (Trionic). See
Fuel injection, basic function
.
See also
Brief description
ORVR.
