Are you refering to the yellowish line up by the Brake Booster in the above picture? it connects to the Switch over valve, and the other end to the ALDA, the square thing in the IP. there is a line from the rear of the intake manifold that goes to the same SO Valve. this is a boost line.

The yellow pod below the SO Valve is a check valve for the vacuum system for the door locks, fuel door and trunk locks. there are 2 yellow lines that go into the cabin, one goes to the Drivers door, and the master vac switch diverts the vac to the various door pods for lock and unlock. the other yellow line with grey stripe goes to the Vac Supply Tank in the trunk above the fuel tank. this is only for the door locks.

This thread explains it.
http://www.peachparts.com/shopforum/diesel-discussion/160169-w123-vacuum-interlock-diagram.html


Charlie

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there were three HP ratings on the OM616...

1) Not much power
2) Even less power
3) Not nearly enough power!! 240D w/auto

Anyone that thinks a 240D is slow drives too fast.

80 240D Naturally Exasperated, 4-Spd 388k DD 150mph spedo 3:58 Diff

We are advised to NOT judge ALL Muslims by the actions of a few lunatics, but we are encouraged to judge ALL gun owners by the actions of a few lunatics. Funny how that works