An engine emission control metering valve includes a metering ball valve element operatively connected to an electrically-energized linear actuator that includes a stationary magnet and a moving coil concentric with the magnet. The coil has a different axial length than the magnet such that application of a current to the coil causes coil-generated magnetic flux to axially push the coil away from the magnet. Coil movement translates into movement of the metering valve element through the wedging action of a cam element driven by the coil movement.
