oxygen sensors and triple catalytic converters play a crucial role in complex vehicle structures, working together to reduce exhaust emissions and improve vehicle environmental performance. There is a close relationship between them, and the working state of oxygen sensor has a great influence on the performance and lifespan of tri catalytic converters.
How oxygen sensors and Three-Way Catalytic Converters Work
How oxygen sensors work
Oxygen sensors are key feedback sensors in electronic fuel injection engine control systems and are usually installed in exhaust pipe. Their main function is to monitor oxygen content in the engine's exhaust gases and indirectly reflect the air-fuel mixture entering the engine. Oxygen sensors are generally divided into front and back oxygen sensors. The front-end oxygen sensor in the exhaust manifold monitors the oxygen content of the exhaust gases after cylinder combustion in real time and transmits this information to the engine control unit. High exhaust oxygen levels in the exhaust indicates a thin mixture, with ECU adding fuel injection. Low oxygen levels indicates a rich mixture, and ECU reduces fuel injection to ensure a complete and efficient combustion process. The rear-mounted oxygen sensor is mounted behind the tri catalytic converter. Its function is to monitor the oxygen content of the exhaust gas treated with a tri catalytic converter. By comparing the front and back oxygen sensors data, ECU was able to determine the effectiveness of the triple catalytic converter.
How a three-phase catalytic converter works
Tri catalytic converter is a device used to purify vehicle exhaust gases. It consists mainly of ceramic substrates and metal coated with catalysts. It is installed in the exhaust system and reduces environmental pollution by chemically converting carbon monoxide (CO), nitrogen oxides (NOx) and hydrocarbons (HC) from the exhaust gas into carbon dioxide (CO2), water (H2O) and nitrogen (N2). In order to achieve efficient purification, the tri-catalytic converter must operate under proper gas-oil ratio conditions, and oxygen sensor is the key part to ensure accurate control of gas-oil ratio.
Effects of Oxygen Sensors on the Three-Way Catalytic Converter
Effects on conversion efficiency of the Three-Way Catalytic Converter
A functioning oxygen sensor ensures that the engine operates at an optimal gas-oil ratio, thus maximizing the efficiency of the triple catalytic converter for the conversion of harmful gases in exhaust gases. However, when the oxygen sensor malfunctions, it was unable to accurately monitor oxygen content in the exhaust gas, leading the ECU to receive error messages and make incorrect fuel injection adjustments. Excessive concentration or dilution of the mixture will lead to incomplete combustion, resulting in an abnormal entry of the exhaust gas composition into the tri catalytic converter. For example, when the mixture is too abundant, unburned fuel enters the tri catalytic converter and continues to burn under the action of the catalyst, causing the catalytic converter to overheat and affecting its efficiency in converting harmful gases. If this anomaly persists for a long time, the purification performance of the tri catalytic converter will gradually decline, weakening its ability to convert pollutants such as carbon monoxide, hydrocarbons and nitrogen oxides, leading to excess vehicle exhaust emissions.
Blockage the Three-Way Catalytic Converter
Faults in Oxygen sensors can also cause blockages in triple catalytic converters. When the oxygen sensor malfunctioned, engine combustion worsened, leading to a large amount of carbon deposits. The exhaust gas carries this carbon deposit away, and it quickly builds up in the stomata of the tri catalytic converter, which can cause blockages. Also, if the oxygen sensor is broken and too much or too little fuel is delivered into the injector, it can cause incomplete combustion. This can cause unburned fuel to build up in the tricatalytic converter, which makes the blockage even worse. A blocked three-way catalytic converter can slow down the flow of exhaust, raise engine backpressure, and damage engine performance, which can lead to less power and more fuel use.. Severe congestion can even cause engine malfunction.
Shortening the service life of triple catalytic converters
Oxygen sensor failures leads to abnormal mixture concentrations, reduced conversion efficiency and blockage of tri catalytic converter, which accelerates aging and damage and greatly shortens its service life. In normal use, the triple-catalytic converter can be used for a long time, but if the oxygen sensor fails, it may require to be replaced early, greatly increasing maintenance costs.