Carol electronic throttle said throttle valve is to control the air entering the engine a controllable valve, gas into the intake pipe and gasoline mixed into combustible gas mixture, thus the combustion of acting. It is connected to air filter, the next engine cylinder, is known as the engine's throat. Traditional cable and electronic throttle two, the traditional engine throttle control mechanism is through the cable (soft wire or rod, and the other end is connected to the gas pedal throttle. At the other end of the connecting throttle linkage plate and work. The electronic throttle valve is mainly through the throttle position sensor to control the opening angle of the throttle valve according to the engine energy, thus adjusting the intake quantity.

Electronic throttle are electric liquid type, linear type electromagnet, step into the motor and DC servo motor type four, Carol electronic throttle said but electro-hydraulic mode and step into the motor due to the control accuracy is not high, linear electromagnetic is due to the required electric power consumption is big, rarely in car application, DC servo motor is very good overcomes the above two kinds of circumstances, thus in the car is applied more widely. In addition, the throttle valve also need to be replaced regularly, the length of time depends mainly on the quality of the air filter, oil quality, vehicle driving road conditions and other factors.