Abstract: A method and apparatus for cleaning a combustion engine having, an intake and combustion chamber having a fuel injector injection device, an oil lubrication system, a catalytic converter and a fuel supply tank. Various solvents are introduced from bulk supply sources into the crank case and into the combustion chamber and into the fuel supply to clean an engine by the introduction of predetermined solvents in a predetermined sequence to clean the engine, the fuel supply tank, the oil lubrication system and the catalytic converter. As chemicals gasify and pass through the catalytic converter, clogging creosote deposits are released thus improving the flow of exhaust through the system improving efficiency and gas mileage.