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Common oxygen sensor defects

Date: 2021-05-23        Clicks: 472

1. Oxygen sensor poisoning

Oxygen sensor poisoning is a common and difficult defect to prevent, especially for the car that often uses petrol with lead. Even the new oxygen sensor can only work several thousand kilometers. If only a slight lead poisoning, and then use a box of unleaded petrol, can eliminate the surface lead of the oxygen sensor, make it back to normal work. However, due to the high exhaust temperature, Lead invades the interior of the sensor, hinders the diffusion of oxygen ions and renders the oxygen sensor invalid. Right now, it can only be replaced.


Additionally, silicon poisoning of the oxygen sensor is common. In general, silicon dioxide generated by combustion of silicon compounds contained in gasoline and lubricating oil, and silicon gas emitted by improper use of silicone rubber gaskets will fail the oxygen sensor, The rubber washer must be selected and installed correctly during repair, and the solvent and anti-adhesive agent other than those specified by the manufacturer must not be coated on the sensor.


2. Carbon deposition


Due to the low combustion of the engine, the carbon deposition forms on the surface of the oxygen sensor, or deposits of oil or dust enter the oxygen sensor, which will prevent or prevent outside air from entering the oxygen sensor, so that the oxygen sensor output signal is inaccurate, and the ECU cannot correct the air-fuel ratio over time. Carbon deposition is mainly caused by increased fuel consumption and emission concentration. At this point, if the sediment is removed, normal operation will be restored.


3. Ceramic fragmentation of the oxygen sensor


The ceramic of the oxygen sensor is hard and fragile. Knocking with hard objects or blowing with strong air flow can cause breakage and failure. Therefore, particular attention should be paid to addressing the problem and replacing it over time.


4. The heating resistance wire is burned

For the heated oxygen sensor, if the heating resistance wire is ablated, it is difficult to ensure that the sensor reaches the normal operating temperature and loses its function.


5.The internal circuit of the oxygen sensor is broken.


6.Inspection of the oxygen sensor's appearance colour


Remove the oxygen sensor from the exhaust pipe and check if the ventilation hole on the sensor shell is blocked and if the ceramic core is damaged. If damaged, replace the oxygen sensor.