EMISSION CONTROL SYSTEM
The vehicle components that are responsible for reducing air pollution. This includes crankcase emissions; evaporative emissions and tailpipe exhaust emissions. Crankcase emissions consist of unburned fuel and combustion byproducts. These gases are recirculated back into the engine for reburning by the Positive Crankcase Ventilation (PCV) system. Evaporative emissions are the fuel vapors that seep out of the fuel tank and carburetor. They are prevented from escaping into the atmosphere by sealing the fuel system and storing the vapors in a vapor canister for later reburning. Tailpipe exhaust emissions consist of carbon monoxide (CO), unburned hydrocarbons (HC) and oxides of nitrogen (NOX). This formation of these pollutants is minimized by various engine design features, careful control over fuel calibration and ignition timing, and the EGR system. The pollutants that make it into the exhaust are "reburned" before they exit the tailpipe by the catalytic converter. The emission control system is an integral part of the engine, and should not be tampered with or disconnected. This is especially true on vehicles with computerized engine controls and/or those that must be subjected to mandatory emissions testing.
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