Question regarding EGR and other emissions parts

[lsmalley]

The first picture shows the EGR valve. Now when is this supposed to have vacuum going to it? I know it holds a vacuum because I tested it and also I connected the line that is also circled in the pic and I watched the EGR diaphragm contract. I'm also at a loss because looking at the EGR and the nozzle, how does the vacuum work? There is only one way a vac line connects to the EGR, but that line doesn't apply suction does it? Isn't the suction supposed to be pulling from the manifold? Someone please help me figure this out, I am constantly getting CODE 16 which is the EGR. Thanks

Second part of this post is the CODE 11 I am getting which is the Air Injection System. When is there supposed to be vacuum from either of the lines in the picture? Is there supposed to be a constant vacuum or does at happen at certain times? The only line I am getting a constant supply of vacuum from is from the long vac line that cuts across the distributor cap and plugs into the check valve that splits off into a Y against the firewall.