I have isolated an HVAC vacuum leak down to somewhere upstream of the green vacuum tube shown in the pic below (in front of the vacuum actuator). The green tube connects to a rubber wye right below the actuator so the vacuum leak is somewhere upward from the picture.

I can't see where the green line runs but I am guessing the leak is somewhere at the other end where the tough plastic tube goes in to rubber. Wondering if anyone knows where this green line routes to and how to get access to that area!

My car has run rough for years because of small vacuum leaks and it turns out the last of these are right in the dash area. It would be great to fix these and have a vacuum tight system once again.

 

remove the dash pad and you can see where these blue and green vacuum tubing connects to several "T" splicers.

if you don't know how to remove the dash pad, let us know.

 

Dash removal: removing the front screws and pulling out the vent bezels -- anything else involved?

As for the leak, I'm guessing the rubber fittings may be the cause given there age. Are the rubber fittings still available from somewhere? I've been replacing the old rubber hoses with silicon ones that hopefully won't give me as much trouble.

 

the pad's vent grilles do not need to be pulled, they come out with the dash pad.

remove the end / corner black plastic finishers first, you can see them when you open the front doors.

the rubber "T" or "Y" can be found at auto parts stores, they are the 1/8" hole or smaller rubber splicers.

there is a vacuum solenoid downstream of the area shown in your picture, I'm sure you've tested it already?