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Home >> Audi >> 2019 >> A4 Premium Plus >> Repair and Diagnosis >> Engine Performance >> Engine Control Systems >> Generic Scan Tool [DBPA] (General Information) >> Generic Scan Tool >> Description And Operation >> Exhaust Systems >> Emission Control
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Emission Control

The primary emission control component is the catalytic converter, which breaks down the gaseous pollutants in the exhaust gas (CO, HC and NOx). Catalytic converters are installed as close as possible to the engine so that they can quickly reach their operating temperature and therefore be effective in urban driving. It also bears a sound-absorbing function, especially to the higher frequency portion of the engine combustion noise.