What to Do If a Sedan Fails the Exhaust Emission Test?
1 Answers
If a sedan fails the exhaust emission test, you can try methods such as keeping the engine warm and regularly cleaning the three-way catalytic converter. Here are the details: 1. Keep the Engine Warm: Do not turn off the engine while idling, and rev the engine in neutral for 3-5 minutes before the inspection. Taking a cold car to the inspection line is unwise. The optimal working temperature for the three-way catalytic converter is between 400 to 800 degrees, and it takes a long time to reach 400 degrees from a cold start. Revving the engine for a few minutes before the inspection can quickly raise the temperature of the three-way catalytic converter above 400 degrees and maintain it for a while. 2. Regularly Clean the Three-Way Catalytic Converter: The three-way catalytic converter must be cleaned every 10,000 kilometers, and it is best to clean it once before the biennial inspection. Domestic gasoline has high sulfur and phosphorus content, which forms chemical complexes on the surface of the oxygen sensor and the three-way catalytic converter. Carbon deposits and particulate matter in the fuel system and intake tract can also pollute the three-way catalytic converter. This can lead to poor exhaust flow, increased backpressure, wasted fuel, reduced power, and diminished or even failed purification function of the three-way catalytic converter, shortening its lifespan of 100,000-200,000 kilometers by 30,000-50,000 kilometers. In severe cases, it can block the three-way catalytic converter, causing the vehicle to catch fire.