These questions pertain to a 1989 420 SEL, 223, 000 KM.

1. Could someone tell me the part name, part number, and what is the purpose of the device shown in the photo, that has the 2 vacuum lines going to it, and is red in colour? It's located in the foward half on the right side, on top of the engine.

2. Next, when the engine is hot, there is no vacuum at the EGR valve. Is this proper operating procedure?

3. I disconnected the vacuum hose to the egr valve, when the engine was hot and there was no change in the way the engine was running. Using a Mityvac, I also applied 20 in. hg. vacuum to to egr valve and there was no change in the way the engine was running. Is this proper operating procedure?

4. Next, that little red vacuum valve shown in the pic, was connected to the EGR valve. The red valve had no vacuum to either side. Is this correct? I would have thought one side of it should have had a vacuum. I couldn't trace the other line very far, it disappeared under the air intake.

5. There was another vacuum valve, similar to the red one, but a little forward and closer to the drivers side. What is this valve called? It had 2 hoses, and neither one had a vacuum, when the engine was hot. Is this proper operating procedure?

6. Finally, the electric change-over valve, located forward of the passenger side front fender, had 20 in. hg. on one hose and zero on the other. Is this correct for a warm engine?

Any and all insight into these conditions is sincerely appreciated.

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1989 420 SEL