hope it helps.... FWIW.... toyota calls them the BVSV (Bimetal Vacuum Switching Valve) think they are like 48 bucks....
i dont mess with factory carbs much but i dont believe its crucial to operation.... you might just block it off see what it does, same for just looping it, think it has something to to with the egr valve..(not charcoal canister like i thought)
personally i run a weber... only one vac line, but i have no emissions
