The need to control the emissions from automobiles gave rise to the computerization of the automobile. Hydrocarbons, carbon monoxide and oxides of nitrogen are created during the combustion process and are emitted into the atmosphere from the tail pipe. There are also hydrocarbons emitted as a result of vaporization of gasoline and from the crankcase of the automobile. The clean air act of 1977 set limits as to the amount of each of these pollutants that could be emitted from an automobile. The manufacturers’ answer was the addition of certain pollution control devices and the creation of a self adjusting engine. 1981 saw the first of these self adjusting engines. They were called feedback fuel control systems. 

In my seminar, I am giving a brief idea of emission standards in light and heavy vehicles. Some of the more popular emission control devices installed on the automobile are: EGR VALVE, CATALYTIC CONVERTER, AIR PUMP, PCV VALVE, EVAPORATIVE CONTROL SYSTEM.