What are the reasons and solutions for unqualified vehicle exhaust emissions?

[TaliaMarie]

Reasons and solutions for unqualified vehicle exhaust emissions are as follows: 1. Oxygen sensor failure: There are generally two oxygen sensors, one located behind the exhaust manifold and the other behind the three-way catalytic converter. The oxygen sensor is responsible for detecting the oxygen content in the exhaust. It sends signals to the ECU, which then adjusts the air-fuel ratio based on these signals. If the oxygen sensor is damaged, the ECU cannot accurately adjust the air-fuel ratio, leading to either a too rich or too lean mixture, resulting in unqualified exhaust emissions. Solution: Replace the oxygen sensor. 2. Three-way catalytic converter failure. Solution: Replace the three-way catalytic converter. 3. Poor gasoline atomization. Solution: Replace the gasoline in time. 4. Oxygen sensor malfunction. Solution: The vehicle's oxygen sensor needs to be replaced.