
Originally Posted by
rabbitnothopper
the vac ports on the throttle body and intake:
the second port on the intake next to the brake booster hose is for a secondary vac line to the breather hose on the valve cover
if your valve cover doesnt have the secondary port (it doesnt) then just cap it
the one you refer to on the TB which faces the VC is an accessory port
it connects to one of several things:
2 way valve (cis-basic)
vacuum amplifier
decel valve
EGR
or
AC
id have to dig through my 78 photos but you can look yourself at the "Before" shot to see (see signature links)
and my 81 has the secondary vac port on the valve cover & intake
on my 78 with CIS-basic i removed a bunch of vacuum lines and other things
only 3 vac total now and they are all on the distributor vacuum advance
car runs and drives fine
...looking more closely
i know VW/audi decided to change SOOO many things through the CIS years
but damn
i noticed you dont have a CSV (5th injector)
how hard is that car to start?