What is the main function of an oxygen sensor in a vehicle?

The primary function of an oxygen sensor in a vehicle is to monitor the amount of oxygen present in the exhaust gases. This monitoring is crucial for the engine management system, which relies on accurate data to optimize the air-fuel mixture entering the engine. By measuring the oxygen levels, the oxygen sensor helps ensure that the combustion process operates efficiently, promoting better fuel economy and reducing emissions.

When the oxygen sensor detects an imbalance in the air-fuel ratio, it sends a signal to the engine control unit (ECU), which can then make adjustments. This feedback mechanism is vital for maintaining the engine's performance and compliance with environmental regulations. Additionally, a well-functioning oxygen sensor contributes to the overall health of the vehicle's emission system, preventing potential failures and enhancing engine longevity.

This role of the oxygen sensor is foundational to automotive diagnostics, as a malfunctioning sensor can lead to increased fuel consumption and elevated emissions, which underscore its essential function in the vehicle's operation.