A regulating device for general automobile utilizes automobile batteries, the plug of the lighter, or the DC output of the engine to obtain power. It has a voltage recognition circuit; when voltage is ≧12.9V, the circuit is started up; when the voltage is ≦12.8V, the circuit is cut off; as a result, the storaged batteries can be protected effectively. When the automobile is started, the circuit will generate pulse energy of 5KHz-10KHz; the pulse has the function of clamping voltage reversely and therefore will eliminate the electromagnetic induction ripple derived from the lightering and fuel feeding circuit, shorten the primary and secondary induction time of lighter coils, quicken the on/off action of a fuel injection needle valve, and improve sprayability effects, make combustion more fully and cut down the carbon deposits; torque can be increased, emission can be cut; accordingly, the whole automobile performance will be improved greatly.