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 (4A-GE)
4. Throttle Position Sensor
5. Oxygen Sensor
6. Intake Air Temperature Sensor
7. Intake Manifold Absolute Pressure (4A-FE)

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.