What is the working principle of an oxygen sensor?
3 Answers
The working principle of an oxygen sensor is: using a ceramic sensitive element to measure the oxygen potential in the vehicle's exhaust pipe, calculating the corresponding oxygen concentration based on the chemical equilibrium principle, in order to monitor and control the air-fuel ratio of combustion, ensuring product quality and compliance with exhaust emission standards. The function of the oxygen sensor is: to determine whether there is excess oxygen in the exhaust after engine combustion, and to convert the oxygen content into a voltage signal transmitted to the engine computer, enabling the engine to achieve closed-loop control targeting excess air, ensuring that the three-way catalytic converter has high conversion efficiency for hydrocarbons, carbon monoxide, and nitrogen oxide pollutants in the exhaust, thereby maximizing the conversion and purification of emission pollutants.
The oxygen sensor plays a significant role. It's installed on the exhaust pipe to primarily measure the oxygen content in the exhaust gases. Its working principle is based on a chemical trick: inside the sensor, there's a piece of ceramic material, with one side exposed to hot exhaust gases and the other connected to ambient air. When the oxygen concentration in the exhaust changes, a voltage difference is generated across the ceramic. This voltage signal is sent to the engine control unit (ECU), which then determines whether the air-fuel ratio is too rich or too lean. If there's more oxygen, it indicates less gasoline is being burned, and the ECU increases fuel injection; if there's less oxygen, it reduces the fuel amount. This closed-loop adjustment ensures more complete combustion, saving fuel and being environmentally friendly. I remember once when my car's check engine light came on, and after checking, it turned out the sensor was aged. Replacing it immediately improved fuel efficiency, and the exhaust stopped smelling bad. I recommend checking it every 20,000 kilometers to prevent this small component from causing bigger issues.
As a seasoned driver, I have some insights about the oxygen sensor. It's actually a clever little sensor that monitors oxygen changes in the exhaust system to adjust fuel injection. Its working principle is quite straightforward: when exhaust gases pass through the sensor, the internal ceramic element generates electrical signals based on oxygen concentration. The signal level tells the computer whether to increase fuel supply. For example, when oxygen levels are high, the electrical signal is low, prompting the computer to inject more fuel; conversely, it reduces fuel injection. This dynamic adjustment helps maintain the engine in optimal condition, reducing waste and pollution. Once, my car's fuel consumption suddenly increased, and upon inspection, I found the sensor was dirty. After cleaning, it returned to normal. Paying attention to it during maintenance saves both money and hassle.
