·         Heat escaping from the cylinders and the engine. Not all of the energy created in combustion is able to drive the car.

·         Friction between moving parts converts some of the energy to heat which is dissipated to the environment. Keeping your engine well lubricated will help reduce this loss.

·         Pumping fuel to the engine. Since your gas tank is beneath your engine, your car must expend energy to move it into the engine.

·         Incomplete combustion. Your engine cannot completely combust all of the fuel during the cycle. Some of the fuel is not burned and is wasted.

·         Braking. Energy is dissipated through heat thanks to friction.