* Fuel Injection: The ECM precisely controls how much fuel is injected into the engine's cylinders based on various sensor inputs (like throttle position, engine speed, air temperature, etc.). This ensures optimal fuel efficiency and power.
* Ignition Timing: The ECM determines the precise timing of the spark plugs firing to optimize combustion and minimize emissions.
* Air/Fuel Ratio: The ECM monitors and adjusts the air/fuel mixture to maintain the ideal stoichiometric ratio for efficient combustion. This is often done using sensors like the oxygen sensor (O2 sensor).
* Transmission Shifting (if automatic): In many cases, the ECM also controls the shifting points of the automatic transmission to optimize fuel economy and performance.
* Emissions Control: The ECM manages various emissions control systems, such as the catalytic converter, EGR (Exhaust Gas Recirculation) valve, and evaporative emission control system (EVAP).
* Vehicle Speed Sensor Input: The ECM receives input from the vehicle speed sensor and uses this information to adjust various parameters, including transmission shifting and fuel delivery.
* Other Sensors and Actuators: The ECM receives information from numerous other sensors (e.g., coolant temperature sensor, mass airflow sensor, throttle position sensor) and controls actuators (e.g., throttle body, fuel injectors, ignition system) to maintain optimal engine operation.
* Diagnostic Trouble Codes (DTCs): The ECM monitors itself and various engine systems for malfunctions. If a problem is detected, it stores a diagnostic trouble code (DTC) that can be retrieved using a scan tool. This allows for diagnosis and repair.
Essentially, anything related to the engine's performance, efficiency, and emissions is heavily influenced or directly controlled by the ECM. It's a very complex system that relies on a network of sensors and actuators to function properly.
