What are the solutions for failing emission tests?
2 Answers
The solutions for failing emission tests are: 1. Accurately determine the cause of exceeding the standard based on the steady-state simplified working condition test values of the exhaust. If the test value is above NO1000, the cause is catalytic converter poisoning. If the test value is NO2000, the cause is catalytic converter failure; 2. If the catalytic converter has failed, further determine whether it is reversible or irreversible failure; 3. Reversible catalytic converter failure can be resolved by using catalytic converter regeneration products for regeneration maintenance. If the vehicle has been driven for more than 100,000 kilometers, it is recommended to also perform catalytic converter cleaning maintenance; 4. Irreversible catalytic converter failure requires replacement of the catalytic converter, and it must be replaced with an original equipment manufacturer (OEM) part.
I was really worried when my car failed the last emissions test due to excessive exhaust emissions. It turned out to be caused by severe carbon buildup on the oxygen sensor leading to an overly rich fuel mixture. The problem was solved after spending 300 yuan to replace the sensor. Older cars are also prone to incomplete combustion due to excessive spark plug gaps or aging ignition coils, which requires thorough troubleshooting. Pay special attention to the catalytic converter - I've seen a neighbor's car with a clogged converter from long-term use of low-quality fuel. Mechanics often recommend cleaning the fuel injectors and throttle body, but if carbon deposits are too severe, the entire exhaust system may need replacement. Before the annual inspection, remember to fill up with 95-octane gasoline and drive on the highway - the high temperatures can burn off some carbon deposits. If all else fails, you might have to pay a few hundred more to get it sorted through alternative channels. Failing emissions tests is a common issue with older vehicles, making regular maintenance absolutely crucial.
