The role of oxygen sensor

Monitor the gas mixture ratio:

The oxygen sensor continuously monitors the oxygen content in the exhaust gas from the engine, thus indirectly reflecting the mixing ratio of air and fuel entering the engine. This helps the engine control system (ECU) to adjust the fuel injection quantity to maintain the best theoretical air-fuel ratio (about 14.7:1), which is the most effective proportion of burning fuel.

Reduce exhaust emissions:

By ensuring that the engine operates at the optimal air-fuel ratio, the oxygen sensor helps to reduce the emission of harmful gases such as carbon monoxide (CO), hydrocarbons (HC) and nitrogen oxides (NOx), which is very important for environmental protection and compliance with emission standards.

Improve fuel economy and performance;

Maintaining a correct air-fuel ratio not only reduces emissions, but also improves fuel efficiency, because fuel can burn more completely. In addition, it also helps to maintain the best performance and responsiveness of the engine.

Three-way catalytic converter monitoring:

The front oxygen sensor (located in front of the three-way catalytic converter) monitors the combustion of the engine, while the rear oxygen sensor (located behind the three-way catalytic converter) monitors the efficiency of the catalytic converter. The reading of the post-oxygen sensor can help diagnose whether the catalytic converter is aging or invalid.

Part of the closed-loop control system:

Oxygen sensor is a key component of engine closed-loop control system. It provides real-time feedback to ECU, so that ECU can dynamically adjust fuel injection quantity and ignition timing to adapt to various driving conditions and environmental factors.

Prolonging engine life: By maintaining ideal combustion conditions, the oxygen sensor helps to prevent the engine from overheating and carbon deposition, thus prolonging the service life of the engine and reducing maintenance costs.

Improve driving experience: optimized combustion efficiency means smoother power output and better acceleration performance, which brings more pleasant driving experience to drivers.

Fault detection and diagnosis:

If the oxygen sensor fails, it may not be able to accurately feed back the oxygen content in the exhaust gas, which will cause the ECU to receive the wrong signal, which may lead to unstable engine operation, increased fuel consumption and excessive emissions. At this time, the fault diagnosis system may light the "Check Engine" warning light on the instrument panel and store the fault code so that the maintenance personnel can locate the problem.