Abstract: Interior parts of gasoline engines are readily cleaned by a method comprising the steps of connecting an a cleaning liquid supply pipe having a gas supply port thereon airtightly to a port of an intake pipe of the engine below a throttle valve-attached position of the engine; operating the engine to draw cleaning liquid in the form of liquid drop and simultaneously drawing continuously a gas having an oxygen concentration of less than 20 vol. % into the intake pipe; and exhausting the cleaning liquid having been brought into contact with the internal parts of the engine with an exhaust gas.

Abstract: Interior parts of gasoline engines are readily cleaned by a method comprising the steps of connecting an a cleaning liquid supply pipe having a gas supply port thereon airtightly to a port of an intake pipe of the engine below a throttle valve-attached position of the engine; operating the engine to draw cleaning liquid in the form of liquid drop and simultaneously drawing continuously a gas having an oxygen concentration of at least 20 vol. % into the intake pipe; and exhausting the cleaning liquid having been brought into contact with the internal parts of the engine with an exhaust gas.

Abstract: Interior parts of gasoline engines are readily cleaned by a method comprising the steps of connecting an a cleaning liquid supply pipe having a gas supply port thereon airtightly to a port of an intake pipe of the engine below a throttle valve-attached position of the engine; operating the engine to draw cleaning liquid in the form of liquid drop and simultaneously drawing continuously a gas having an oxygen concentration of less than 20 vol. % into the intake pipe; and exhausting the cleaning liquid having been brought into contact with the internal parts of the engine with an exhaust gas.