Hello, I recently purchased a 1988 T2. After noticing a surging idle I started to investigate. I found a vacuum line with a screw in it. It appears to start underneath the upper intake manifold.

i have looked at the FSM and through the forums. It looks like it could be the primary air bleeder from a photo I found, but I have no clue where it should actually be plugged into. I also found a capped hardline (see photo).

any help would be greatly appreciated.

Thanks

 

Have you smoke tested the intake system to find any leaks?

 

That’s next on the agenda. I’m just trying to figure out where this vacuum line goes.

 

a smoke test might show where it goes, i think is what he means. the only thing in that area are the ports near the throttle body.

 

The leak looks like it’s coming from above the turbo somewhere.

 

it might go to the EGR, the diaphragm tends to rip and create a vacuum leak so they might have just omitted its functionality. try a little harder to trace that line to see where it goes. the smoke test seems to point to a brittle turbo to intercooler coupler that is leaking.

 

wrong thread, disgregard

 

I would second the EGR. Tracing it shouldn't be too hard. No Guessing.