What Causes Unstable Idling Speed in a Van?

[DelRose]

The reason for unstable idling speed in a van is excessive carbon buildup in the throttle body. When this occurs, the throttle body can be removed and cleaned. After cleaning and reinstalling the throttle body, it is essential to perform a computer re-calibration; otherwise, it may lead to increased fuel consumption. The throttle body acts as the engine's throat, controlling the amount of air entering the engine. It is installed on the engine's intake pipe. When the driver presses the accelerator pedal, the throttle opening increases, allowing more air to enter the engine cylinders. After the sensor detects the increased air intake, it sends a signal to the ECU (Engine Control Unit), which then commands the fuel supply system to increase fuel injection. As a result, the engine speed rises.