W124 92 300D Ignition Vacuum switch

[pdrayton]

My ignition vacuum switch over valve seems to be a problem. The supply and return line to the ignition switch are fine, so is the shutoff valve (tested with mityvac.

So i'm thinking it must be the ignition vacuum switch. But I'm a little concerned it could be something to do with the new ignition switch I put in. It works fine except that it doesn't spring back from START like it should. You have to manually move it back to RUN after the starter has started the engine.

Is there anyway that could be the problem? Another reason I'm doubtful is with the ignition off, the switch doesn't hold any vacuum. With the ignition in RUN, it holds vacuum. Does that sound like a broken vacuum switch? I'm not sure what it is supposed to do.

What section is the ignition in the FSM? I've looked and looked, didn't find it anywhere.

Thanks,

Paul