The device consists of an injection valve (10, 16, 23) with at least two injection nozzles fitted in the inlet manifold (8) in front of the inlet port of a combustion chamber of the internal combustion engine and a feed device (15) for the supply of air to the inlet port connected to several inlet valves (4, 5) of said engine. In the inlet manifold in front of the injection side of the injection valve there is an air deflector by means of which air is directed to one of the jets of fuel from the injection valve in such a way that said jet is deflected by the air in certain operating conditions. For use in multi-valve internal combustion engines.