What is the function of the secondary oxygen sensor?

[Ariana]

The function of the secondary oxygen sensor is to detect the oxygen concentration in the exhaust and send a feedback signal to the ECU. The ECU then adjusts the fuel injection quantity of the injector to keep the air-fuel ratio of the mixture near the theoretical value. The oxygen sensor is a critical feedback sensor in the electronically controlled fuel injection system. It plays a key role in controlling vehicle exhaust emissions, reducing environmental pollution, and improving fuel combustion quality in the engine. If the oxygen sensor fails, the ECU of the electronic fuel injection system will not receive information about the oxygen concentration in the exhaust pipe, making it unable to perform feedback control on the air-fuel ratio. This can lead to increased fuel consumption and exhaust pollution, as well as engine issues such as unstable idling, misfires, and surging. Therefore, it is essential to promptly troubleshoot or replace the faulty sensor. Vehicles are equipped with both front and rear oxygen sensors, which work in tandem to achieve optimal performance.