MattMiller

Long story short, this line goes to nowhere. comes off the thingy majiggy on the strut support bar.

joejoe

Mine runs to the rear of motor to a 4 way splitter.

MattMiller

I have found a 4 way line connector under the booster. 1 side has a cap. Is this what you are talking about? I'm chasing leaks and trouble shooting hard shift, no cruise and my heater vents. Anyone know what this line is supposed to do?

MainePorsche

Matt,
That portion of the image in the red circle - where/what does the rubber elbow attach to ? Is this the union of another line that goes elsewhere ?

MattMiller

Its some kind of valve mounted on the cross bar

MainePorsche

Not that familiar with the 86.
Quick look up showed me it is either the air bleed valve or diaphragm valve. Nonetheless, these both receive vacuum from same splitter back yonder.

MattMiller

We are starting to think the booster is bad

Kevin in Atlanta

Start here with the vacuum diagram posted on Roger's website.

85-86 vacuum diagram

Randy V

A valve attached to the crossbrace is typically the idle advance for the AC system.

Idle speed is increased when the AC is turned on to handle the increased engine load.