Deceleration

This is a CLOSED LOOP mode. During deceleration the following inputs are received by the PCM:
- Engine coolant temperature
- Manifold absolute pressure
- Engine speed
- Throttle position
- Exhaust gas oxygen content
- A/C control positions
- Battery voltage

The PCM may receive a closed throttle input from the Throttle Position Sensor (TPS) when it senses an abrupt decrease in manifold pressure. This indicates a hard deceleration. The PCM may reduce injector pulse width or the number of injectors firing per engine revolution. This helps maintain better control of the air/fuel mixture (as sensed through the O2S sensor).