Re: diesel and petrol
Very Good Question…
Here U go the Technical Details 
Like petrol, diesel fuel is blended from various petroleum components produced in a refinery. However, diesel contains components that have a boiling point range of approximately 200°C to 350°C. Vapour pressure is not an important consideration in the production of diesel, since the fuel does not need to change to a gas in a diesel engine. Diesel engines inject liquid fuel into the cylinder, unlike petrol-powered engines with carburettors. However, temperature can have an effect on the operation of diesel fuel in an engine. At low temperatures, diesel fuel may thicken and restrict the flow of fuel to the cylinder. Oil companies produce diesel blends that are formulated for specific climates and times of the year to prevent problems in cold weather.
