Hyundai Elantra AD Quiz
Engine Control System/Fuel System

Variable Charge Motor Actuator (VCMA) Description and Operation

In this manual: Engine Control System/Fuel System
General Information — 9Engine Mechanical System — 84Engine Electrical System — 60Emission Control System — 24Engine Control System/Fuel System — 90Automatic Transmission — 92Drive Shaft and Axle — 20Suspension System — 31Steering — 20Restraints — 50Brake System — 63Body (Interior and Exterior) — 214Body Electrical System — 221Heating, Ventilation, and Air Conditioning — 71
~1min read

Description

The Variable Charge Motor Actuator (VCMA) is installed at the intake manifold inlet. It consists of a DC motor that drives the VCM valve and a position sensor that detects the position of the VCM valve. The VCM system creates a swirl of the intake air flowing into the combustion chamber of each cylinder by closing the VCM valve during cold start conditions. This swirl effect reduces cold start emissions by improving fuel atomization.

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