What does the function of an oxygen sensor primarily monitor?

The function of an oxygen sensor primarily monitors the engine's air/fuel mixture. This sensor measures the amount of oxygen present in the exhaust gases before they exit the vehicle. By analyzing the data from the oxygen sensor, the engine control unit (ECU) can determine whether the air/fuel mixture is too rich (too much fuel) or too lean (too much air). Maintaining the correct air/fuel ratio is crucial for optimal combustion, fuel efficiency, and minimizing harmful emissions.

When the oxygen sensor provides feedback, it allows the ECU to adjust the fuel injection and air intake accordingly to ensure efficient engine performance and compliance with emission regulations. Therefore, the information gathered by the oxygen sensor is vital for the engine's overall functionality and environmental impact.