Variable Cylinder Management

The system operates through controlling the flow of hydraulic engine oil pressure to locking mechanisms in the cam followers.

When the VCM system disables cylinders, an "ECO" indicator lights on the dashboard, Active Noise Cancellation (ANC) pumps an opposite-phase sound through the audio speakers to reduce cabin noise, and Active Control Engine Mount (ACM) systems reduce vibration.

The VCM hydraulic circuit control is defaulted open, meaning that the engine has to build up enough oil pressure on initial startup to disable the rear bank of cylinders.

This unique type of oil consumption has led to premature failure of parts like spark plugs, catalytic converters, engine mounts, pistons/rings, and cylinder walls.

[citation needed] Owners of vehicles equipped with VCM frequently face vibration problems due to engine motor mount malfunction while ECO mode is enabled.