* Fuel injection: The PCM determines the amount of fuel injected into the engine based on various sensor inputs (like throttle position, engine speed, oxygen sensor readings, etc.).
* Ignition timing: It controls the precise timing of the spark plugs firing to optimize combustion efficiency and power.
* Engine speed and torque control: It monitors and regulates engine speed and torque to maintain smooth operation and prevent damage.
* Transmission control (if automatic): The PCM controls shift points, torque converter lockup, and other aspects of the automatic transmission's operation.
* Emission control: The PCM monitors and controls various emission systems to ensure compliance with environmental regulations. This includes things like the catalytic converter and evaporative emission control system.
* Sensor monitoring: The PCM constantly monitors a multitude of sensors throughout the engine and transmission system, detecting potential problems and illuminating warning lights when necessary.
* Security system interaction: On many vehicles, the PCM interacts with the vehicle's anti-theft system.
In short, the PCM is a vital component that ensures the engine and transmission function correctly, efficiently, and safely. A malfunctioning PCM can lead to a wide range of problems, from poor performance to complete engine failure.
