The invention provides an air-liquid heat exchanger for a motor vehicle fluid-flow circuit (2, 3), the heat exchanger comprising a plurality of tubes (4) extending between two fixing and distribution blocks (5, 6) to which the ends of the tubes are coupled, each of said two blocks comprising: a face (10, 13) facing the other block and carrying internal coupling members (15) for coupling the corresponding ends of the tubes (4) to the block in question; an internal distribution channel (17) interconnecting the internal coupling members (15); and an external coupling member (19) for coupling the block in question and its internal distribution channel (17) to the fluid-flow circuit (2, 3) of the vehicle. At least one (5) of the two blocks has at least one ventilation nozzle (23) passing therethrough between its face (10) carrying the internal coupling members (15) for coupling tubes (5) to said block, and its opposite face (9).