I have an 84 300D with a vacuum line that is disconnected and no obvious place where it should have been connected.

It is the green/yellow line that comes through the firewall. I have confirmed that it goes into the climate control system. According to the vacuum chart, it should go into a check valve with a red/grey line from the vacuum reservoir. I cannot find the red/grey line anywhere.

The only check valve that goes into the firewall at the same point has a yellow and a yellow/black line. I traced the yellow to the front driver's door, and the yellow black goes up towards the instrument panel then I lose it.

My climate control buttons always send the air to defrost and the outside vents, which I have read is the defaul position, so possibly it is not getting any vacuum due to the disconnected line.

Does anyone know where this green/yellow line should be connected?

Thanks.

Hi Fredyarvin, I looked in my service manual for 123 chassis and it shows the following: green/yl line goes from forward port on brake boost line to a check valve, then to 3 way conn. one side goes to vac resovoir, the other goes to vac rotary switch for a/c in middle of dash up in front of climate control panel. ther the vacuum is distributed to the actuators(pods) for center vents, leg room flaps, defrost etc. Hope this helps you out, good luck bubba 2