Fuel Charging and Controls—5.0L

The fuel delivery sub-system consists of a high-pressure in-tank mounted fuel pump (FP) 9H307 and a fuel filter/reservoir delivering fuel from the fuel tank through a 20 micron fuel filter to a fuel charging manifold assembly.

The fuel charging manifold assembly incorporates electrically actuated fuel injectors directly above each of the engine's intake ports. The injectors, when energized, spray a metered quantity of fuel into the intake air stream.

A constant fuel pressure drop is maintained across the injector nozzles by a pressure regulator. The regulator is connected in series with the fuel injectors and is positioned downstream from them. Excess fuel supplied by the pump, but not required by the engine, passes through the regulator and returns to the fuel tank through a fuel return line.

Each injector is energized once every other crankshaft revolution in sequence with engine firing order. The period of time that the injectors are energized (injector "on time" or pulse width) is controlled by the vehicle's powertrain control module (PCM). Air entering the engine is monitored by speed, pressure and temperature sensors. The outputs of these sensors are processed by the powertrain control module (PCM). The computer determines the needed injector pulse width and outputs a command to the injector to meter the exact quantity of fuel.