Variable Cylinder Management

Variable Cylinder Management (VCM) is Honda's term for a Variable Displacement technology. It uses the i-VTEC system to disable one bank of cylinders during specific driving conditions (for example, highway driving) to save fuel. Unlike Chrysler and General Motors' pushrod systems, Honda's VCM uses overhead cams.

It uses a solenoid to unlock the cam followers on one bank from their respective rockers, so the cam follower floats freely while the valve springs keep the valves closed. The engine's drive by wire throttle allows the engine management computer to smooth out the engine's power delivery, making the system imperceptible. Vehicles with VCM are equipped with an "economy" light, but it does not always correspond to the VCM system's operation.