A turbocharger compressor housing apparatus comprises a compressor housing and diffuser. These components are configured to provide an interference fit when assembled. An annular projection extends outwardly from one of such components toward the other of the components and engages the other of the components to form an annular joint. One of the compressor housing and diffuser comprises a recess positioned to collect debris generated during the interference fit to prevent the debris from reaching the annular joint. A second recess can be provided at the opposite side of the projection to accommodate deformation of the projection during assembly of the diffuser and compressor housing. The recesses can be annular and can, along with the projection, be included in the diffuser.