Chasing Vacuum Leaks (Throttle Body)

[Rad_Comanche]

So my 86 2.5L has the typical problem of having several vacuum leaks. I have been slowly chasing them down, but today showed me something new.

 

We got a new smoke machine at work, and they let me use it on my truck today. I was excited to finally find my vacuum leaks, but I did not expect everything the smoke revealed.

 

The first one was obvious, the oring that seals the top and bottom of the air intake. I am not concerned with that one just yet, since it is before the fuel is injected. I would love to know if anyone has found an oring/gasket/seal that fits in there though, as I would like to replace it eventually.

 

The second leak looked to be the EGR, I believe it was coming out from under the bladder. I cannot remember if this is supposed to be open by default or not, but I have others I can replace it with.

 

The third one took me by surprise. It looks like there is a leak along the shaft that holds the throttle plate and such on the body. When I looked inside by the plate, I saw there is a gap leading out of the throttle body, which ends at the piece below circled in red.

 

It is hidden behind the throttle mechanism, and I have no idea what it is. Smoke was practically billowing out of this area, and I could not tell if it was the piece circled above, or a leak along the shaft itself.

 

I was prepared to replace the entire throttle body when I got home tonight, but both of my spares are from 87+ trucks, so the vacuum ports are different. Typical one off 86 problems.

 

So my question is, what is that piece above jutting out from the throttle body, and can it leak, or is it just the shaft, and I need to replace the whole thing?

[cruiser54]

First off, every vacuum leak needs to fixed when it's found. You can't just arbitrarily assign a value to it

 

Seems like I post these almost every day.

 

 

[Rad_Comanche]

3 hours ago, cruiser54 said:

First off, every vacuum leak needs to fixed when it's found. You can't just arbitrarily assign a value to it

 

Seems like I post these almost every day.

 

 

I realize now that the way I worded my post sounds like I was trying to do what you describe. However, I am not trying to assign value to each leak, rather I am listing my findings of what needs to be done, and any observations I made after my smoke test.

 

I will fix every leak, but my main concern in this post is whether my entire throttle body is trash or not, hence my questions about what that port inside is, and the piece it seems to run to on the outside.

 

As I mentioned before, my throttle body is an 86 model, so it is not the same as the one pictured above. The dead end ports are used on mine, and I have replaced the rubber boot that goes over those four ports with hose for each one.