Circuit Description

The Sequential Multiport Fuel Injection (SFI) system is controlled by the Powertrain Control Module (PCM). PCM energizes the solenoid coil of each fuel injector individually by completing the electrical circuit to ground. When energized the fuel injector solenoid operates the solenoid plunger, allowing pressurized fuel to be injected into the intake port of the cylinder. The fuel pump will pressurize the fuel rail and the fuel injectors as long as the engine is cranking and the PCM is receiving the ignition system reference pulses.