Variable Charge Motion Actuator (VCMA)
Variable Charge Motion (VCM) is a system that changes the direction of intake air. The component is installed on the engine head and composed of a flap that changes air flow, a motor for the flap, and a flap position sensor. Under cold start or during low-RPM driving, it closes the flap and changes the flow of intake air (creating a swirl), which can enhance the performance of cold start and lower cold start emissions.