Air/Fuel Ratio (EFI)
Data received by the ECU from the following sensors is used to control injection pulse width:
1. Water Temperature Sensor
2. Engine and Vehicle Speed Sensors
3. Intake Air Volume (Airflow Meter)
4. Throttle Position Sensor
5. Oxygen Sensor
6. Intake Air Temperature Sensor
The duration of the injection pulse width determines the precise air/fuel ratio for the engine under all operating conditions. The extremely fast reaction time of fuel control by the ECU enables the emissions to stay within a very narrow range. This in turn, allows for the use of a three-way catalytic converter on most vehicles.