Excuse me whilst I change my trousers . <| sep |> I agree . As it happens , I ' m studying a unit on internal combustion engines at uni right now , and the differences are surprisingly large . As I ' m sure everyone in rcars already knows , petrol gasoline engines are generally better for short trips e . g . to the supermarket or around town , while diesel is better for long journeys involving cruising on a motorway . This is partly due to petrol engines ' ability to warm up quicker , and partly due to the lowend torque from a diesel engine allowing it to sit at a lower engine speed than a similar petrol engine to produce a similar amount of power . With that in mind , it shouldn ' t be surprising to hear that some cities in Europe like Paris are considering banning diesel cars altogether . On the other hand , you ' re right for America , diesel cars are probably preferable .