Precision-machined housing ensures proper air flow to engine as required by ECU during changing load requirements. Precision-machined solenoid components generate magnetic force to actuate plunger. Anodized aluminum housing resists corrosion better than regular passivation treatment. High-temp polyester coating on solenoid coil wire ensures proper function during cyclic exposure to elevated temperatures. Machined surface finish on mounting plate improves air-sealing capabilities against manifold surface.