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Is it necessary to warm up the car before an exhaust emission test?

1 Answers

LouisDella

07/30/25 7:42am

It is necessary to warm up the car before an exhaust emission test. Methods of exhaust emission monitoring: There are four methods for monitoring vehicle exhaust emissions: single idle speed method, double idle speed method, steady-state operating condition testing method, and simple transient operating condition method. The single idle speed method has been phased out due to its simplicity and higher detection data limits. The simple transient operating condition method is more scientific than the double idle speed method and the steady-state operating condition testing method, providing more accurate detection data. It is currently the most advanced vehicle exhaust emission detection technology in the world. Automotive environmental exhaust emission standards: The limit for carbon monoxide is 6.3g/km, and the total limit for hydrocarbons and nitrogen oxides is 2.0g/km. Vehicle exhaust emission testing is based on whether the smoke opacity value meets the standard, and whether the emissions meet the standard is mainly determined by the vehicle testing data. The smoke opacity value is used to confirm whether the vehicle meets the standard.

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