How Does an Oxygen Sensor Work?
1 Answers
The basic working principle of an oxygen sensor is: under certain conditions, it utilizes the oxygen concentration difference between the inside and outside of the zirconia element to generate a potential difference. The greater the concentration difference, the larger the potential difference. The oxygen content in the atmosphere is 21%, while the exhaust gas from rich mixture combustion contains virtually no oxygen. The exhaust gas produced by lean mixture combustion or misfires contains more oxygen, but still significantly less than the oxygen content in the atmosphere. Additional information about oxygen sensors is as follows: 1. Under high temperature and the catalysis of platinum, the oxygen attached to the oxygen sensor is completely consumed, thus creating a voltage difference. A rich mixture outputs a voltage close to 1V, while a lean mixture outputs a voltage close to 0V. 2. Based on the voltage signal from the oxygen sensor, the air-fuel ratio is controlled to adjust the fuel injection pulse width. Therefore, the oxygen sensor is a key sensor for electronic fuel metering control.