Jon C. Martin

I was working on the vacuum system on my 1987 truck when I noticed something strange...on the top passenger side of the carburetor there are three vacuum ports that have rubber vacuum caps with little extensions on them (see attached). Two of these caps have vacuum lines connected to them. These two lines go to a Coke-can sized black cylinder behind the fuze box.

Now, as far as I can tell there is no way for vacuum to pass through these caps, and they look original, so I'm baffled...why would the factory seal off a vacuum port but still run a vacuum hose to it? Why have this part on the truck, and run vacuum hoses to it, when it's apparently not operating on vacuum?

b/s rules

may have something to do with california emissions. i have the exact same thing on mine. it's a 87 22r in a 91 standard cab. i ended up completly doin away with as much vacuum as possible. try 22r carbs.com

algranger

Ahhhahaha! The caps are indeed factory. Toyota used them on certain setups, i have trucks with and without. The hoses attached to them are not factory someone must have put them on later, not noticing they were caps. =
Anyways i've fiddled around with those vacuum ports and they dont affect the way it runs at all, you can just leave them capped. Obviously the mechanism on the other end of the hoses isnt getting any vacuum pressure so you can take it off.
Most all of the stuff under there is useless you can just get rid of it.

b/s rules

yep, what he said

drew303

you really only need the vac advance lines for the motor to run (if everything is capped off).

fyi