Sequential Multi-Port Fuel Injection (SFI)
WARNING: This page is about a different car, the 2013 Ford F-350 Super Duty and 2013 Ford F-250 Super Duty. However, it is still accessible from the selected car via links, so may be relevant.
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
The fuel charging and controls system is:
- a Sequential Multi-Port Fuel Injection (SFI) system.
- Pulse Width Modulated (PWM).
- 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 basic fuel requirement of the engine is determined from the data supplied to the PCM by the MAF sensor, which measures the amount of air being drawn into the engine.
The various sensors detect any changes in the operating conditions and send signals to the PCM. This permits the PCM to control the opening duration (pulse width) of the fuel injectors and maintain optimum exhaust emission control and engine performance for all operating conditions.