Abstract: The engine has a device for injecting fuel, preferably at high pressure, into the cylinder of cylinders, a device adjusting the injection advance in dependence on the load, and a controlled ignition device, the said engine being arranged to use a fuel other than a petroleum product, preferably an alcohol based product, and being characterized in that its dimensional characteristics are determined to supply a volumetric compression ratio between 12 and 20, preferably between 15 and 18 and in particular close to 16, and in that the device adjusting the injection advance is such that it supplies, at least for starting, a high value of advance, particularly of the order of 180.degree..