Fuel Charging And Controls

Fuel Charging and Controls


Sequential Multi-Port Fuel Injection (SFI)

WARNING: Do not smoke, carry lighted tobacco or have an open flame of any type when working on or near any fuel-related component. Highly flammable mixtures are always present and may be ignited. Failure to follow these instructions may result in serious personal injury.

The fuel charging and controls system consists of the following:

- Throttle Body (TB)
- Fuel injectors
- Fuel rail
- Fuel rail pressure and temperature sensor
- Fuel Pump Driver Module (FPDM)

The fuel charging and controls system is:

- a Sequential Multi-Port Fuel Injection (SFI) system.
- pulse-width modulated.
- Mass Air Flow (MAF) controlled.

Fuel is metered into each intake port in a sequential firing order. Fuel injectors pulse to follow engine firing order, in accordance with engine demand on a tuned intake manifold.

The PCM controls the fuel injection system. Injector pulse width is varied to control the amount of fuel flow. Varying fuel pump output controls fuel pressure. The PCM commands the fuel pump driver module, which directly controls the fuel pump. The TB is electronically controlled by the engine management system. Throttle plate angle is changed electronically in response to throttle pedal movements initiated by the driver.


Throttle Body (TB)

The TB:

- controls air supply to the intake manifold by electronically positioning the throttle plate.
- is not adjustable.

Refer to Throttle Body.


Fuel Injectors

The fuel injectors:

- are electronically operated by the PCM.
- atomize the fuel as the fuel is delivered.
- each have an internal solenoid that opens a needle valve, which injects fuel into the intake port in the cylinder head.
- are deposit resistant.

For removal and installation, refer to Fuel Rail and Fuel Injector - Exploded View Fuel Rail and Fuel Injector - Exploded View and Fuel Rail Fuel Rail.


Fuel Rail

NOTICE: The fuel injectors and the fuel rail must be handled with extreme care to prevent damage to sealing areas and sensitive fuel-metering orifices.

The fuel rail:

- receives fuel from the fuel supply tube.
- delivers fuel to the fuel injectors.

For removal and installation, refer to Fuel Rail and Fuel Injector - Exploded View Fuel Rail and Fuel Injector - Exploded View and Fuel Rail Fuel Rail.


Fuel Rail Pressure and Temperature Sensor

The fuel rail pressure and temperature sensor:

- measures the pressure and temperature of the fuel rail and sends these signals to the PCM.
- uses intake manifold vacuum as a pressure reference.

For removal and installation, refer to Computers and Control Systems Information.


Fuel Pump Driver Module (FPDM)

The FPDM:

- receives signals from the PCM.
- duty cycles the fuel pump.

For removal and installation, refer to Fuel Pump Driver Module (FPDM) - Explorer, Mountaineer Service and Repair or Fuel Pump Driver Module (FPDM) - Explorer Sport Trac Service and Repair.