What are the symptoms of a faulty oxygen sensor in a Skoda Octavia?

[Javier]

Skoda Octavia oxygen sensor failure symptoms: If an oxygen sensor issue occurs, the specific manifestation depends on the fault code definition. If it's a sensor heating circuit problem, generally replacing the oxygen sensor directly suffices. If there's an issue with the oxygen sensor signal, further inspection of the engine combustion condition is required. The Octavia's oxygen sensors are installed in the exhaust pipe (typically the first one before the three-way catalytic converter and the second one after it). The functions of oxygen sensors are as follows: Detecting oxygen concentration: One is located before the three-way catalytic converter to measure oxygen concentration before catalytic treatment, while another is positioned after the converter to measure post-catalytic oxygen concentration. These dual feedback mechanisms help adjust fuel injection more precisely for current operating conditions. Reducing exhaust emissions: In engines using three-way catalytic converters to minimize exhaust pollution, oxygen sensors are essential components. Since the air-fuel ratio's deviation from the theoretical value drastically reduces the three-way catalyst's purification capability for CO, HC, and NOx, oxygen sensors in the exhaust pipe monitor oxygen concentration and send feedback signals to the ECU. The ECU then adjusts fuel injector output to maintain the air-fuel ratio near its theoretical value.