The paper presents a fuel system of a dual fuel spark ignition engine with a multipoint methanol and gasoline injection into the inlet valve area. The engine is fitted with double electronically controlled injectors. The system allows the engine operation on gasoline and methanol separately as well as combustion of the mixture of both fuels of any given alcohol content. The preliminary tests have been performed on a 4-cylinder spark ignition engine – Fiat 1100. The paper presents comparative results of the tests of an engine fuelled with gasoline and methanol. The performed tests showed an advantageous effect on the engine efficiency, the level of nitric oxides and hydrocarbons in the exhaust. A quick combustion of methanol increases the thermal load of the engine, which in turn may lead to an improper operation of the ignition system.