Hi Bill.
Let me take a crack at it: The check valve that is between your timing cover and air pump diverts air to either the intake ports of the intake valves or directs air to the air cleaner. When you 1st start the car, the solenoid engages to direct air to the intake thus, quickening the rate the catalyst heats to reduce cold-start emissions. The o2sensor heats quicker, sends a signal in which the diverter is then sw. to direct air from your pump to the air cleaner. Once the the car is at running temp, the air just stays directed to the air cleaner...I think. Being that the air pump has a clutch, it may engage off at some point while the engine is at temp. I removed my whole system when I redid my 380; I tapped the holes in the intake ports to 7mm and put metric hex plugs w/ loctite in. The car nontheless still passed del. strict sniff. If you remove the parts you describe and plug the front timing w/ a22mm fitting, it will be fine......for a while. Because the carbon buildup within those intake ports will be sig in time if no air ever pushes through. You would see this if you ever removed your intake to change gaskets or do any other service. I was told this would happen from a German mb tech. I also saw in the cd of the dowelled plugs that the european models had in place of the plugs I made. The dealer doesn't carry these plugs. les