Abstract: A molded plastic article has an injected or foamed molded section (12) with at least one insert part (24) with a part (16A-16D) which emerges from the molded section (12). The insert part (24) penetrates a deformable molded body (34) which forms a sealing element for the mold cavity when the injected or foamed molded section (12) is produced in the mold cavity of a molding tool. A process for producing the molded plastic article involves locating the molded body (34, 46) together with the insert part in the region of an edge of the mold cavity, closing the tool unit so that the molded body undergoes deformation and the mold cavity in the region of the emergence of the insert part from the mold cavity is sealed by the molded body.