hubturn

95 Cab idling pretty bad and after reading all I could, I figured it was an Idle Air Control Valve. Replaced it(used one)to no avail. Then I notice that it's a bit loud on the drivers side and I start moving the brake booster vacuum lines - that Rube Goldberg collection of hoses and fittings that start at the front of the intake manifold and run just inward of the valve cover on the drivers side. Found a cracked plastic check valve. How could that happen? Epoxied it up and now running good, but ordered a new one because you can't EVER get plastic to stay glued. Three bucks of technology that Audi is charging me $57 for. So there's a new one for the idle problem list that has to be checked.

Lago Blue

It is helpful to future readers that folks write-up their fixes. We are often concurrently on parallel paths:

https://www.audiworld.com/forums/sho...7&postcount=12

hubturn

That link is to the easy vacuum lines that the manual transmission has. I'll post a photo when the parts come in. Here's the diagram of the difference for the automatic.