Abstract: An auxiliary device for attachment to internal combustion engines for the purpose of reducing the objectionable polluting constituents of the exhaust gases therefrom and reducing the amount of fuel consumed. The device functions to reduce pollution by reducing the production of objectionable exhaust gas contaminants through more efficient combustion of the fuel. Efficient fuel consumption is achieved by means for presenting the fuel to the carburetor in preheated atomized liquid form for admixture with air prior to introduction to the combustion chambers. The auxiliary device comprises a housing having separate passages for circulation of liquid fuel and water in heat exchanging relationship. In addition to reducing pollution, use of the device effects fuel savings through more efficient fuel consumption.