If I understand correctly, you can get the center vent to work using jumpers to operate the solenoid and you can get it to work by connecting the vacuum line to another solenoid, right? If so, then the solenoid and the vacuum pod are both working, which is nice since the pod failure is common and hard to repair (have to pull the dash).

Which ACC unit does the 1982 model have? Does it have vertical or horizontal pushbuttons?

You may have a bad contact in the ACC. That would prevent the solenoid for the center vents from being energized. Another possible cause is a damaged wire. You will have to do some tracing. It's a slow process.

Another thing you might want to consider is to modify the system so that the center vents are open all the time. That way, you will get heat out of the center vents in the winter, which is very nice. Do this by removing the glove compartment and then the rubber sleeve that connects the air box to the center vents. Now you can see the metal lever that opens the flap to the vents. It is held to the flap by a plastic pin. Remove the pin and open the flap with your hand, jamming it under the lever. Put the sleeve and the glove box back and you're done.

If you're gonna go veg, do it properly and put in a two-tank heated system. Too many W123's have been ruined by poorly installed junk conversions.

Jeremy

__________________

"Buster" in the '95

Our all-Diesel family
1996 E300D (W210) . .338,000 miles Wife's car
2005 E320 CDI . . 113,000 miles My car
Santa Rosa population 176,762 (2022)
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"Oh lord won't you buy me a Mercedes Benz."
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