Fuel Delivery and Air Induction: Description and Operation

The fuel system used is of the recirculatory type.

The fuel tank is mounted across the car behind the rear passenger seats.

The system schematic is shown in Fig. 1. Fuel is drawn from the fuel tank (1 Fig. 1) into the in-tank fuel module (2 Fig.1) by the fuel pump (3 Fig.1 ), with the fuel passing through a venturi on the fuel pump pressure side.

A70 micron filter is incorporated at the inlet port of the module to prevent ingress of particle contaminants.

Fuel is pumped from the base of the fuel tank through a flexible hose to an in-line filter (5 Fig.1). From the filter, fuel flows through underfloor pipework to the front of the vehicle where flexible hose connects the underfloor feed pipe to fuel rail.

The fuel rail is mounted on the engine (7 Fig.1). A fuel pressure regulator referenced to manifold vacuum (6 Fig.1) controls fuel line pressure and maintains a constant pressure across the fuel injector (FI) nozzles. Pressure is kept constant within the range 241.30 to 310.25 kN/sq. m (35 to 45 psi).

Spill return fuel from the fuel pressure regulator is returned to the in-tank module through return hoses and underfloor pipe. A 70 micron filter is used in the return inlet of the module to capture debris that may be present in the fuel rail or return line at initial start-up and so prevent it from entering the system.

Both the feed and return ports of the module use non-return valves for safety.

Figure 1:

1. Fuel Tank
2. Fuel Pump Module (FPM)
3. Fuel Pump
4. Tank Pressure Control Valve
5. Fuel Filter
6. Fuel Pressure Regulator
7. Fuel Rail
8. Fuel Injectors (FI)
9. Inlet Manifold