Fuel System

A powertrain control module (PCM) (12A650) accepts input from various engine sensors to compute the required fuel flow rate necessary to maintain a prescribed air/fuel ratio throughout the entire engine operational range. The computer then outputs a command to the fuel injectors (9F593) to meter the appropriate quantity of fuel.

The system will automatically sense and compensate for changes in altitude (i.e., from sea level to mountainous regions) and also permits push-starting the vehicle should it become necessary (manual transmission only).

The fuel delivery subsystem consists of a high-pressure in-tank mounted fuel pump (9350), and a fuel filter/reservoir delivering fuel from the fuel tank (9002) through a chassis-mounted 20-micron fuel filter to a fuel injection supply manifold (9F792).

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

A constant fuel pressure drop is maintained across the fuel injectors by a fuel pressure regulator (9C968). The fuel pressure 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 (6007), passes through the regulator reservoir input and returns to the fuel tank through a fuel return line.

7.5L Simultaneous Multiport Fuel Injection (MFI) Engine

Item	Part Number	Description
1	9E926	Throttle Body
2	9424	Intake Manifold, Upper
3	9F483	EGR External Pressure Valve
4	9F792	Fuel Injection Supply Manifold
5	9F715	Idle Air Control Valve
6	9C968	Fuel Pressure Regulator
7	9F593	Fuel Injectors

Item	Part Number	Description
1	9D930	Fuel Charging Wiring
2	9C968	Fuel Pressure Regulator
3	9F792	Fuel Injection Supply Manifold
4	9424	Intake Manifold, Lower
5	9F593	Fuel Injector