Port S and V should not commingle. If they do the diaphragm has a hole in it. All you need to do is blow in one of the ports and air shouldn't come out the other port. If the diaphragm is ripped it wont be able to open the valve and allow vacuum to pass through port R and O on the opposite side of the amplifier and then to the egr valve. When vacuum from the spark port on the carb is greater than vacuum from the venturi port on the carb the amplifier valve is opened allowing vacuum to the egr. Also between the amplifier and egr is a load control valve. It dumps the vacuum to the egr when venturi vacuum is present. I'm assuming all this complicated stuff is supposed to close the egr valve during idle and full power. I've been studying this for the past week but still don't have a complete grasp on it. Time to go to the shop and hook up vacuum lines. Wish me luck. Here is the diagram I'm gonna follow and a picture of the load control valve with amplifier.