Induction System
WARNING: This page is about a different car, the 2014 Ford F-150. However, it is still accessible from the selected car via links, so may be relevant.
The GTDI is Pulse Width Modulated (PWM).
Fuel is metered directly into each combustion chamber. Fuel injectors pulse to follow engine firing order, in accordance with engine demand.
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.