Second up:

Pull the carpeting and passenger kick panel from the right side.

Carefully remove the carpeted piece of cardboard that sits on the right side of the transmission tunnel.

Next to the CCU, to the right, you'll see a set of six electromechanical switchover valves in a vertical series. Unscrew the manifold as an assembly and pull it out a bit so you can get to the ports.

The vertical ports are the vacuum supply ports. You'll see that they all originate at one supply hose. Check the condition of the supply hose at each valve and be sure that they are not leaking.

The horizontal ports go to the pods.

Remove each hose from the horizontal port and connect it to a Mityvac (using an extension hose, of course). Pump up the Mityvac and see if the pod holds vacuum. Usually, it will hold with very little bleed, or it will fall instantly.

Report back with results. There are six switchover valves that go to six pods. #1 is on the bottom IIRC.