Chevrolet Repair: chevy van, chilton manuals, throttle body injection

Question
i have a 1986 chevy van with a 305 engine g20 on  my thermostat housing is a built in vacuum selinord it has 4 outlets the vacuum line has been pull fron their place and i dont know where each one plugs in to on this housing is there anyway you can pull up a picture of the thermostat housing and the vacuum line and show me where they go,or a site that would have a picture of this.thank for all the help you have given us.i think this is my problem?

Answer
Hello Darnell,
I don't have a picture, but at the public library, in the refference section, they have shelves of manuals, and will have one for that car.
In addition, they have the Mitchell, Motors, and Chilton manuals.
Most of them have a section of vacuum hose diagrams.

I have a 1987 Mitchell, but no way to scan a page.
But in the 5.7L V8 Heavy Duty C20, it shows a temp vac switch for operating the EGR valve, as well as vapor canister purge.
It looks like the port closest to the engine connects to ported vacuum from the carb base, and the second one from the thermostat connects to the egr valve, and the vapor canister purge port.
If there is a third port on that valve, I can remember seeing foam rubber on some of them as they were to allow the vacuum to bleed off, but my book doesn't show it.
In my 87 book, all the G20's were throttle body injection.
So really, you need to look at the 86 book.

And that is a temperature vacuum control valve.

Van