So, all my vacuum pods are original in the 87 300E, and they all still work (fingers crossed) with the exception of the center vent actuator. When I turn the A/C on, the actuator does not open the flap for center vents like its supposed to. However, if I stick a rod through the vent grille, and gently push on the flap, it will slowly start lowering itself down and stay down until I shut the car off. I have to do this every time I turn the a/c on otherwise it just won't open by itself.

Any idea why the pod won't pull the flap down by itself? Is it finally shot or could there be some other kind of vacuum leak that's not giving the pod enough power for the initial push?

Thanks much in advance!

-Chris

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Streetside: 1987 Mercedes 300E Petrol Blue/Green
2014 Ford Mustang Grabber Blue
1999 Ford Ranger Green

Dockside: 1968 Eltro 17
1985 Silverton 34C

You need to make sure that there isn't any other vacuum "pods" that leak.

When you ask for center vent operation, there are 3 other diaphragms that get vacuum to CLOSE at the same time.

You need a vacuum schematic & a vacuum hand pump with gauge.

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Pull the glovebox, then use a Mityvac on each vacuum line. Whichever ones do not hold vacuum = done!

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Thanks.
I'm sure I'll fine a few that are leaking.

__________________
Streetside: 1987 Mercedes 300E Petrol Blue/Green
2014 Ford Mustang Grabber Blue
1999 Ford Ranger Green

Dockside: 1968 Eltro 17
1985 Silverton 34C