You are doing fine. Diligence. You are getting there. lucky all LEDs light. You are lucky if you don't smell have antifreeze and have to pull the heater core.

guesses for definitions : (these xcould change accorsding to the user and context)

The motor should be vacuum motor by the driver side strut under hood or the engine. However when someone says flap motors sounds like he is speaking of the plastic cans (actuators).

The servos would be the electical coils that open or shut vac flow into their respective vacuum hose. As I recall there are 12 of these.

To me the actuator is the 2" dia X 3" plastic can with one or two vac ports that vac hose(s) connect(s) to. The other end of the hose connects to the servos often through some plastic fittings. Obviously the fittings and hoses can leak also. Rarely does hose leak rarely does servo not work Actuatiors and fittings often leak.

The actuator has an internal diaphram that is supposed to seal and hold vac on one side and air on the other. It has a metal rod or bar coming out the end that is attached to the center of the actuator internal diaphram. The rod other end is attached to and moves a given flap toward more of an air flow opening or less.

When you key "on" and loose vac you are probably energizing a previously closed electric servo and thus/ opening up a vac path that either leaks or has a large volume of air to remove. Some flaps have a long stroke and take a lot of vaccum pumping to move full actator travel.... takes some time to build up vac in the reservoir. Does your vac pump shut off a few minutes after starting the car with the fan switch off ? If it did you have a good system up to the reservoir and up to the servos. if not fisx that part of the system before going on. If it holds vac/ pump shuts off, you can try the various buttons with the fan wheel on and see if for any of them the vac pump comes back on and keeps running: means a leak in that vac path to that flap actuator. You will probably notice that when the pump keeps pumping for that button you get no air flow where there should be: i.e. flaps not moving. Other checks: You can remove the radio and the ash tray to get access to many of the hoses and servos. put fingers on servos while pushing the HVAC buttons to see if they click. also you can clamp the suspected vac line to see if that stops the leak (vac pump shuts off).

For the check valve test, remove it from the vac hoses and suck on the black port (toward engine) to verify air correctly flows through it in that direction. Then reverse it and suck on the blue port to verify no air comes through it from that direction ( it keeps the vacuum built up in the HVAC system from bleeding into the engine.) A better test is proably to use the vac hand pump on each end, blank off the opposite side with finger and see if it holds vac.

That is just one way to check things with unit in the car, I'm sure there are others, probably better. refer to E 38 diagrams for locations and hose colors.

There are 6 servos in the front and two on the right side (pass), and i think two on the left. The flaps, each with actuators and servos that i count are
1) Rear pass
2) front floor
3) Defrost
4) front face
5) cowl fresh air (two flaps act as one)
6) fresh air into heater core
7) Fresh air into AC evap core

Good luck.

84 745
85 735

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