pollutant from car exhaust

Four of them can be the pollutants from car exhaust. NO2 is the generated after combustion of some nitro-compound which is put in petrol as anti-knocking agent. Soot is generated if the engine is not in perfect condition. Lead compound may generated if the pertoleum is not unleaded. SO2 is generated is the petroleum is not desulfurized. To my opinion, SO2 should not be the major pollutant since the petroleum has been de-sulfurized effectively.

D burn petrol 是不會有so2的