Forester S F4-2.5L DOHC (1998)
EGR Valve: Description and Operation
PURPOSE/OPERATION
Control amount of exhaust gas recirculation. The electronic control module signals the EGR solenoid to switch from ported vacuum to
atmospheric pressure, thereby opening and closing the EGR valve. The EGR valve opens in response to engine driving conditions and provides a
portion of exhaust gas to the cylinders through the intake manifold. EGR valve vacuum signal is picked up from a port upstream from the throttle
valve.