New fast idle air valve produced by Mikuni. These are OE replacement parts produced by the manufacturer for Mitsubishi. If you have having issues with not being able to hold a high idle when it is cold outside, it will be either your idle control servo, or the fast idle air valve. The fast idle air valve acts as a thermostat for air to bypass the throttle plate. As the coolant temperature rises, the valve inside the FIAV closes and seals off the bypass to the throttle plate, which lowers the idle when the engine comes to temperature.