So on my quest to get this working I’m a little stuck . First of all the ball joint on the exhaust vavle at the drivers side was seized up I free this and the flap in the exhaust is free . Took the pipe off the vacuum saucer looking thing pushed the rod up put my finger over the end and it held the push rod up all seems goodthere . But when I got someone to Rev the car is didn’t open or close not sure which . Pipes from manifold seemed ok too . I’ve come across this not sure what it does see pic . Now I can’t blow though the pipe that sticks straight out . Nor can I when I put 12v power to the part . I’m thinking this could be broken but don’t understand what it does I’m guessing it sends power to it at low revs to shut the drivers side exhaust and at high revs power is taken away so it opens it’s using both exhaust this right ?????? Or is it a pressure vavle the completes a circuit???