CONTROL SYSTEM

① Engine Control Unit         ② Fuel Injection         ③ Upstream Oxygen Sensor         ④ Downstream Oxygen Sensor

Working principle:

The oxygen sensor detects the oxygen concentration in the exhaust gas by generating a voltage. Typical oxygen sensors use zirconia electrodes, which are electrically conductive at high temperatures. The oxygen sensor separates the exhaust gas flow into two parts: one part is the outside air, and the other part is the exhaust gas. Due to the different oxygen concentrations in the two parts, the zirconia electrode generates an electromotive force between the two parts. The ECU determines whether the air-fuel mixture ratio is lean or rich based on this electromotive force.

Maintenance and Breakdown:

Oxygen sensors may fail due to carbon deposits, contaminants, or aging after long-term use. Common symptoms include decreased fuel economy, increased emissions, and engine warning lights coming on. Regular inspection and replacement of oxygen sensors are important measures to maintain engine performance and reduce pollution.

In summary, oxygen sensors play a vital role in the vehicle’s fuel management and emission control systems, ensuring that the engine operates at its best while effectively reducing harmful gas emissions.