The oxygen sensor is an important component of the automotive emission control system. Its function is to monitor the concentration of oxygen in the exhaust pipe and use this information to determine the fuel injection quantity of the injectors, thereby controlling the air-fuel ratio to achieve optimal exhaust gas conditions. However, oxygen sensors are prone to some failures. This article will introduce the common failures and maintenance methods of oxygen sensors.

I. Symptoms of Oxygen Sensor Failure

Decreased Engine Power: If the oxygen sensor fails, it can cause an uncontrolled air-fuel ratio, thereby affecting the efficiency and performance of the engine, leading to a decrease in engine power.

Increased Emissions: If the oxygen sensor fails, it can result in incomplete combustion, leading to increased emissions, including carbon monoxide, hydrocarbons, and nitrogen oxides.

Check Engine Light Illumination: If the oxygen sensor fails, it can cause the check engine light to illuminate, alerting the driver to inspect and repair it promptly.

II. Common Failures of Oxygen Sensors

Oxygen Sensor Poisoning Oxygen sensor poisoning is one of the most common failures of oxygen sensors, especially for vehicles that frequently use leaded gasoline. Oxygen sensor poisoning can lead to a decrease in sensitivity or even complete failure of the oxygen sensor.

Ceramic Fracture of Oxygen Sensor The ceramic portion of the oxygen sensor is prone to fracturing, which can also cause the oxygen sensor to fail.

Oxygen Sensor Circuit Malfunction If the circuit of the oxygen sensor malfunctions, it can prevent the oxygen sensor from functioning properly. In such cases, it is necessary to check the connection of the oxygen sensor's circuit for any issues such as open circuits or short circuits.

III. Maintenance Methods for Oxygen Sensors

Replacement of Oxygen Sensor If the oxygen sensor fails, it usually needs to be replaced. When replacing the oxygen sensor, it is important to select the appropriate model and brand to ensure proper functioning of the new sensor.

Cleaning the Oxygen Sensor If the oxygen sensor is not heavily contaminated, its sensitivity can be restored through cleaning. Generally, ultrasonic cleaners or chemical cleaning agents can be used for this purpose.

Check the Circuit If the oxygen sensor fails, it is necessary to check the connection of its circuit for proper functioning. If any circuit issues are detected, timely repairs should be carried out.

In conclusion, the oxygen sensor is an important component of the automotive emission control system. Its performance and condition directly affect the efficiency and performance of the engine. Therefore, regular inspection and maintenance of the oxygen sensor are crucial measures to maintain the engine in good condition.