lifespan of oxygen sensor 100，000 kilometers is a small hurdle for a vehicle. A car that is not well maintained will enter frequent failures outbreak period. The oxygen sensor is a part that almost no one has thought of replacing., but it is the one that must be paid attention to and replaced Irregular. The main materials of the oxygen sensor are platinum and zirconium oxide. Its service life is generally 8-10 kilometers. There are three types of oxygen sensor failure modes: CO poisoning, sulfur and phosphorus poisoning, lead poisoning, silicon poisoning, and manganese poisoning. The quality of gasoline and lubricating oil has a great impact on the life of the oxygen sensor.
How oxygen sensors workThe oxygen sensor is a measuring component that utilizes ceramic sensitive elements to measure the oxygen potential in the automobile''s exhaust pipe. Based on the principle of chemical equilibrium, it calculates the corresponding oxygen concentration, enabling the monitoring and control of the air-fuel ratio during combustion. This ensures the quality of the product and compliance with emission standards.
The zirconia element within the oxygen sensor functions similarly to an electrolyte. Under certain conditions, it generates an electrical potential difference due to the varying oxygen concentrations on its inner and outer sides. The greater the concentration difference, the larger the potential difference. While the oxygen content in the atmosphere is 21%, the exhaust gas after burning rich mixtures practically contains no oxygen, while that from lean mixtures or misfires contains more oxygen, but still significantly less than in the atmosphere. At high temperatures and catalyzed by platinum, negatively charged oxygen ions adhere to the inner and outer surfaces of the zirconia sleeve. Since there''s more oxygen in the atmosphere than in the exhaust gas, the side of the sleeve exposed to the atmosphere attracts more negative ions than the exhaust side, creating an ion concentration difference that generates an electromotive force.
When the oxygen concentration on one side of the automobile''s three-way catalytic converter is low, a high voltage (0.6 to 1V) is generated between the electrodes of the oxygen sensor. This voltage signal is sent to the vehicle''s ECU for amplification and processing. The ECU interprets high voltage signals as indicating a rich mixture and low voltage signals as indicating a lean mixture. Based on the voltage signals from the oxygen sensor, the computer adjusts the mixture to be as close as possible to the theoretical optimal air-fuel ratio of 14.7:1, either by diluting or enriching it. Therefore, the oxygen sensor is a crucial sensor for electronically controlled fuel metering. The oxygen sensor''s characteristics are fully expressed only at high temperatures (above 300°C at the tip), enabling it to output voltage. It responds most rapidly to changes in the mixture at around 800°C, while its characteristics vary significantly at lower temperatures.
