Device and method for cleaning coked cavities, in particular valves in input channels of a combustion engine

A water-soluble cleaning powder (44) is introduced as a powder jet into the to-be-cleaned cavity, through a compressed gas, while introducing an aqueous liquid (48) into the to-be-cleaned cavity, so that, when the cleaning powder is released into the aqueous liquid, a cleaning fluid is formed in the cavity. By the suction effect of cleaning fluid with the introduced gas, the dirt particles are dispersed out of the cavity along with the cleaning fluid. The amounts of cleaning powder and aqueous liquid are matched, so that the cleaning powder is completely released in aqueous liquid. An independent claim is included for a device for cleaning coked cavities of valves in intake ports of combustion engine.