Fuel Delivery

The fuel delivery sub-system consists of a low pressure fuel pump (mounted in fuel tank), a fuel filter/reservoir and a high pressure electric fuel pump. Pump delivers fuel from fuel tank through a 20-micron fuel filter to a fuel charging manifold assembly. The fuel charging manifold assembly incorporates electrically actuated injectors directly above each engine intake port.

When energized, injectors spray a metered quantity of fuel into intake air stream. On 2.3L and 2.9L engines, all injectors are energized simultaneously (once per crankshaft revolution). On 3.0L engines, the injectors are energized in 2 groups of 3 injectors. Each group is activated once every other crankshaft revolution. On 5.0L engines, a bank of 4 injectors is energized once every crankshaft revolution, followed by second bank of injectors during next crankshaft revolution.

The length of time that injectors are energized (injector "on time" or "pulse width") is controlled by EEC module. A constant fuel pressure drop is maintained across injector nozzles by a pressure regulator.