W201 vacuum system help
 

I've got a 1984 190 E 2.3 .
What is the engine number on this?

Anyway, heater constantly on. I'm going to trouble shoot the vacuum system.

All I have is a Haynes manual and the article John Cacavas wrote sometime ago.

Anyone have any tips for me? Schematics?
When I connect the vacuum line supplying the switchover valve directly to the red heater valve line, the heater valve does close.

What should the idle speed vacuum value be at that point?

Bob
Huntsville, AL