Briefly describe the cleaning method of throttle valve (Figure)
Remove the air inlet bellows at the front of the throttle.
A person turns on the ignition switch of the car without starting the engine, and operates the accelerator cable by stepping on the accelerator, so that the accelerator is in the full open position. A person gently shakes the throttle cleaning tank several times, so that the conduit of the throttle cleaning tank extends into the intake pipe to spray clean the throttle and intake pipe. Wait 10~20min after spray cleaning. If it is not clean enough, you can spray it again. Spray the remaining throttle cleaner on the throttle body and return spring.
Wipe off impurities with cotton cloth, blow dry with compressed air, or turn on the throttle for a few minutes to let the cleaning agent evaporate.
After the throttle is matched, restart the engine, idle for 3~5min, then accelerate for 2~3 times, and control the maximum speed at 3000r/min.
Throttle matching after cleaning the throttle:
The throttle is used to control the air intake, and the accelerator pedal actually controls the opening of the throttle. Then, the control unit adjusts the fuel injection amount (increases the number of fuel injections under heavy load) according to the throttle opening and the opening. When the throttle is dirty, the efficiency decreases and the opening increases, the control unit will make some adjustments and matches. Under normal circumstances, the adaptive adjustment value of idle speed is 1.00.
With the change of engine working conditions (such as the vehicle running for a long time and the throttle body becoming dirty), the cross-sectional area of air flowing through the throttle will become smaller. At this time, in order to stabilize the idle speed, the throttle opening will be appropriately increased. In this way, the adaptive adjustment value of idle speed will increase correspondingly and become greater than 1.00, such as 1.05, 1. 10, etc. But the maximum adjustment value can only be adjusted to 1. 15. If the throttle body continues to be dirty, the air intake is insufficient at idle speed, resulting in unstable idle speed or even flameout. In this case, as long as the throttle body is cleaned, the flameout problem can be solved. However, the adaptive adjustment value stored in the engine control unit has not been modified, and it is still 1. 15, so the throttle opening will still be very large, resulting in excessive engine idling.
Therefore, after cleaning the throttle, it is necessary to reset the throttle and restore the control program and parameters to the original state. If it does not match, the control unit will learn the throttle opening that has been set for a long time, and it will be set in the original position after cleaning, which will lead to engine power drop, jitter and even alarm. The most direct manifestations of mismatch are high idle speed and self-increasing idle speed.
Matching method of throttle valve:
There is no need to re-match the throttle of American and Japanese engines after cleaning. As long as the battery negative pole is disconnected 1 min, the control unit will lose its remaining memory and return to normal.
After cleaning or replacing the throttle valve of Fiat series cars, turn the ignition switch to the on position 10s, turn off the ignition switch, turn on the ignition switch again, start the engine, complete the adaptation of the throttle position sensor, and return to normal idle speed.
When the Volkswagen series throttle valve is matched, it is necessary to input the channel number when using the scanning tool to perform basic functions such as setting, matching and coding.