CO, HC, and NOx not only are harmful to human health, but also harmful to the environment. Governments around the world are trying to reduce the density of this type of pollution from car exhaust. Generally, a car running in a dry area, such as in a desert, would consume more gasoline. On the contrary, a car running in a wet area, such as a sea coast area, would consume less gasoline. In other words, the humidity or water vapor will affect the combustion efficiency of an engine because the specific gravity of gasoline is different from that of water, i.e., the specific gravity of gasoline is lower than that of water, and therefore they can not be compounded together. Before the vaporized gasoline and water enter the combustion chamber, the particles of the gasoline vapor, having light specific gravity, are attached to the water particles. After the water particles enter into the cylinder, the water particles will expand under high temperature and high pressure, and the gasoline particles attached to the water particles will be divided, or become smaller, i.e., the contact area between the gasoline and the air will be increased (mixing efficiency is increased). The oxygen contained in water will augment the combustion effect to provide a complete combustion. Therefore, the horsepower of the engine will be augmented, greater fuel economy will be achieved, and carbon deposits in the cylinder will be reduced. As a result, the service life of the engine will be increased, maintenance costs will be reduced, and the HC and CO exhaust will be lowered. Since water can lower the engine temperature, NOx exhaust will be reduced, decreasing its impact on the environment. This product can provide a plurality of cyclic auxiliary ignition pulses between two original ignition pulses so as to reduce pollution from the car exhaust. This product can be installed in cars that have already rolled out of the factory, improving the combustion efficiency of the engine and reducing the density of pollution from the car exhaust.