Chevrolet Full Size Cars 1979-1989



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Fig. Fig. 1 The vehicle emission control information label includes vacuum diagrams and engine control system adjustment information

There are three sources of automotive pollutants: Crankcase fumes, exhaust gases and gasoline evaporation. The pollutants formed from these substances all into three categories: unburned hydrocarbons (HC), carbon monoxide (CO) and oxides of nitrogen (NO;ix). The equipment that is used to limit these pollutants is commonly called emission control equipment.