What to Do with Vehicles That Fail Emission Standards?

[Sylvia]

Vehicles that fail to meet emission standards can be improved by installing exhaust purification devices. For gasoline vehicles, a three-way catalytic converter with an electronically controlled air supplement system can be installed, while diesel vehicles can be equipped with an exhaust smoke purification device. When vehicle emissions fail to meet standards, the first things to consider are the three-way catalytic converter and the front oxygen sensor. Incomplete combustion of the engine's air-fuel mixture can generate a large amount of carbon deposits, which can accumulate inside the three-way catalytic converter and on the oxygen sensor. Cleaning the three-way catalytic converter and oxygen sensor can resolve emission issues. If, after cleaning the three-way catalytic converter and oxygen sensor, and replacing the spark plugs, the vehicle's emissions still fail to meet standards—assuming there are no faults with sensors such as the air flow meter and temperature sensor—a thorough engine carbon cleaning maintenance should be performed.