Fuel Injection Timing

For fuel injection timing:
- the fuel injectors are energized in the following sequence: 1, 4, 2, 5, 3, 6.
- the period of time that the fuel injectors are energized (fuel injector on time or pulse width) is controlled by the vehicle's Powertrain Control Module (PCM). Air entering the engine is measured by a Mass Air Flow sensor (MAF sensor). This air flow information and input from various other electronic engine control sensors is used to compute the required fuel flow rate necessary to maintain a prescribed air/fuel ratio for engine operation.
- the powertrain control module determines the needed fuel injector pulse width and outputs a command to the fuel injectors to meter the exact quantity of fuel.