1983 300TD wagon Vacuum Issue: on my 300TD wagon the vacuum leaks down (15 minutes) after shutting down the engine. Upon starting the engine it takes about 1 minute for all the door locks (including the rear hatch) to open. The engine shuts off properly and no problem with the power brakes. The other issue is that I need to let the engine run for about 1 minute before the center AC pod will work allowing cold air to come through the the middle vents.

Is this a vacuum reservoir issue or ? Thanks.

Bump

I had a similar issue. Usually it would lose vacuum with a lot of stop-and-go traffic, but the last couple of days it would lock the doors but not unlock, even if it was just a few minutes.

I poked around the vacuum connectors and found the one that had three branches right before the firewall was so loose a couple of the lines just fell out. The worst was the one with a fat yellow plastic thing. I'm surprised it held any vacuum at all.

Anyway, I would check all your rubber connectors and look for anything visibly cracked, broken, or loose. Easy and cheap stuff first on these cars.

-Rog

Have you checked the driver's door lock 3 way vacuum valve? Isolate it by plugging the vac supply line going to it and if the leak goes away, it is likely the culprit.

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85 300D turbo pristine w 157k when purchased 161K now
83 300 D turbo 297K runs great. SOLD!
83 240D 4 spd manual- parted out then junked

I just checked all the vacuum lines/fittings under the hood and did not find any problems. I will check the 3 way valve in the driver's door and report back. Any other suggestions are welcome. Thanks.

That does not check the valve behind the door card (unless you did plug the supply line going to it)

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85 300D turbo pristine w 157k when purchased 161K now
83 300 D turbo 297K runs great. SOLD!
83 240D 4 spd manual- parted out then junked

With the supply line to the 3 way valve plugged should I notice an improvement in my AC middle ducts knowing that my door locks will not work with the supply line disconnected and plugged? Thanks.

As for air that enters the front centre vents This is the same temp all the time never hot its to keep the driver awake . So it said in the book

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84 300D, 82 Volvo 244Gl Diesel