EFI engine throttle body is to control the feed rate of a device from the structure and principle point of view, different models of the throttle body is basically the same. The structure includes: door body, throttle, throttle position sensor, the stepping motor type idle speed control valve (or the idle speed valve), paraffin-type air valve, the throttle valve rocker wheel.
       Control the engine Throttle Body    intake of how much a valve. Is a circular steel plate, the middle one axis, and the throttle cable to connect by cable throttle control. Throttle body of the engine air intake system on one device. Throttle body generally divided into three parts: the actuator, throttle plate and throttle position sensors, which are generally packaged as one. From the edge of the exhaust gas recirculation pipe is to achieve a certain emission standards. Aluminum body are usually, but also a small amount of plastic such as BYD etc.
       Paraffin wax is a type of the induction air valve body, the use of small wax in the solid state, liquid state characteristics of a large volume, through temperature control, low temperature operation (air valve open), high temperature (85 ℃ or so) the air valve is closed.

      Stepper motor type idle speed control valve is the world's most widely used kind of idle speed control device for controlling the opening degree of the bypass air passage of the engine speed to the required value. Automotive permanent magnet stepper motor to the stepper motor, a stepping signal supplied through the computer for switching control, the rotational angle of the rotor turned positive or negative angle of rotation, so that the valve body (screw) for telescopic movement, adjustment to achieve the purpose of the bypass air passage cross-section, so as to stabilize idling, and to achieve the desired idle speed. Throttle position sensor is mounted on the throttle shaft for detecting a throttle opening degree sensor, it signals the computer to calculate the engine load, the ignition timing, exhaust gas recirculation control, idle speed control, and other parameters. A bad throttle body position sensor will cause the acceleration lag and idling issues.
       Focus on cleaning the  Throttle Body  cleaning and throttle bypass air passage near the cleaning do not remove the throttle position sensor, cleaned once a year is sufficient, it is not idle instability problems.

       Some of the engine    Throttle Body  no idle adjustment screw, while others more than a throttle body and idle speed can be adjusted, however, is at the throttle rocker wheel.

       Early in the process the engine is started, two air valves work together, when the engine speed is decreased after the first idle air control valve is closed; as the engine temperature increases to the normal speed is reduced again, then the wax-type air valve is closed, only the idle adjustment screw at the bypass air passage work, so the need to adjust the engine idling the engine temperature normal, and other electrical equipment is not working, so that by adjusting the screw speed and stability at the lowest speed can be.