Heat exchanger, particularly motor vehicle engine charge air cooler

A heat exchanger for a motor vehicle engine, the heat exchanger comprising a housing comprising opposing sidewalk, and an upper wall and a lower wall separating the opposing sidewalls, a heat exchange bundle disposed within the housing and comprising pairs of plates defining fluid circuits for circulating cooling liquid, a collector of the cooling liquid circulating in the heat exchange bundle, and a collector plate forming both a side wall of the collector and one of the opposing sidewalls of the housing, the collector plate comprising a flat connecting part provided with orifices communicating with the fluid circuits of the heat exchange bundle and the flat connecting part being formed without collars adjacent to the orifices, wherein each of the plates of the heat exchange bundle has an end fold bent to form a flat end edge defining an end of the plate, wherein for each pair of the pairs of plates the flat end edge of one of the plates and the flat end edge of the other one of the plates are fixed flat-on-flat to the flat connecting part on opposite sides of one of the orifices of the collector plate without the heat exchange bundle extending into the orifices of the collector plate.