What is the primary purpose of emission systems in engines?

The primary purpose of emission systems in engines is to keep the engine running cleanly and efficiently while controlling emissions, exhaust, and pollutants to reduce harmful gases. Emission systems achieve this by incorporating various components, such as catalytic converters, oxygen sensors, and exhaust gas recirculation (EGR) systems. These components work together to minimize the release of harmful substances, such as carbon monoxide, nitrogen oxides, and hydrocarbon emissions, into the environment.

Controlling these pollutants is essential not only for meeting environmental regulations but also for improving air quality and public health. Effective emission systems allow engines to operate within stringent emissions standards while still providing acceptable performance levels. Thus, the correct answer emphasizes the importance of environmental responsibility and engine efficiency over merely maximizing power or altering the engine's appearance.