I have the 20r on my 79. Yesterday I was cleaning my intake and broke one of the ports off it yesterday. Its hooked to my intake on the bottom where the plate is. I am desmogging my engine so can I block it off or did I mess up something?

 

Pics help a lot..

 

X2!
there are alot of little plastic bits around there...

 

 

 

That looks like the thremal switch for either the egr or evaporative emission. If your doing a de-smog you might not use it. It is not a vacuum leak in its current state.

 

Hey i have that on the 3.0 as well. mine was also broken and i had to replace it. It was a BVSV. And they do tend to break because they are so old. Every truck i seen at the junkyards had them broken.
Here is a link to the page# on my thread where i talk about this.
https://www.yotatech.com/forums/f199...6/index10.html
You can buy these at Autozone/o'reiley etc. Mine only costed about $45. Look through my thread and you'll see what a new one looks like. im not sure what page it is on but i eventually show the pix of when i installed mine on my 3vze. Its the same piece though.

 

Thanks for the reply. If I don't have to use it I dont want to. So if I dont plug it no coolant will come out. Red I will look at your post.

 

I'm eliminating anything unnecessary because im doing a desmog.

 

no because it works as part of your vacuum system. The only way to coolant will come out is if you remove or replace the actual BVSV. Before replacing mine I went ahead and bypassed that BVSV and it ran just fine. But as far as everything I read, that BVSV works as a switch. As the temperature of the coolant underneath that BVSV gets to a certain temp it will open up and allow the flow through those 2 vacuum hoses. I don't know about the 22r but on my 3vze it runs from the Charcoal Canister into the BVSV into somewhere near my throttle or intake plenumn. But I read somewhere that that BVSV is a switch to allow unused gas vapors which are stored in the charcoal canister to be reused. And if you aren't using that then you're obviously getting worse mileage. Something like that dont quote me. But that's what I read. And thats why I decided to get it fixed because having the 3vze as it is already gets me crappy mileage lol so I wanted to fix it at least in case that was true.

 

Ok. See I was thinking that plastic thing was something to do with coolant. I didn't know it had anything to do with fuel.

 

It switches vacuum under certain conditions. Depending on what it's controlling, and depending on what controls it. Coolant, exhaust, etc. It could control emissions components or something else. A vacuum diagram is a useful tool here.