Electronic Variable Orifice (EVO) Actuator

The electronic variable orifice (EVO) actuator is located on power steering pump and contains a solenoid operated pintle valve. Fluid leaving pump passes through an orifice in actuator tip. When EVO actuator is powered by SSPS control module, pintle moves into orifice and reduces power steering fluid flow. As vehicle speed increases, current from SSPS control module increases, and pintle blocks more and more of orifice.