Theory Of Operation

The electronic Fuel Injector is supplied power via the Fused Automatic Shut Down (ASD) Relay Output circuit. The Powertrain Control Module (PCM) provides a pulse width modulated (PWM) signal to the injector's solenoid coil to inject pressurized fuel just upstream of each cylinder's intake valve. Each injector receives a unique pulse width based on that cylinder's fuel requirements. The PCM determines this fuel requirement by monitoring engine operating parameters via various sensors and then calculating the appropriate amount of fuel to be injected. The optimum amount of injected fuel depends on conditions such as engine and ambient temperatures, engine speed and workload, and exhaust gas composition.