Tim968

Working on '92 GTS, verifying HVAC vacuum system integrity using method set out by Mr Plumley (Cut the orange line that feeds the central vent actuator (this is the most common failure point in the system). Using a MityVac, make certain the line that runs up to the actuator will hold vacuum. If it does, use a rubber tube to reconnect the cut ends of the orange line. If the line to the dash doesn't hold vacuum, plug the line that comes from the manifold, no need to plug the end that runs up in the dash). So - on this car, everything checks out correctly, except the central vent actuator - seems likely that the hose is off the fitting at the actuator, or the actuator is shot, or both. WSM Section 87, pg104 doesn't clearly define actuator except as "bulkhead". WSM Sect87, pg109 says "position of bulkhead flap is visible with cover removed from central vent and vent open.

Hmmm - how is this actuator accessed for re&re? I am I about to get way into the dash components?

Thx/T

Rob Edwards

The center console needs to come out.

There's a great writeup in this thread, though it was done on an '87.

https://rennlist.com/forums/928-foru...re-w-pics.html


Since yours is an airbag car, there is a painful 8mm screw you need to get out in order to get the center console out:

https://rennlist.com/forums/928-foru...ole-screw.html

Ed Scherer

Lots of threads on this topic. A few I turned up:

• A/C Vacuum problem. Getting close, please help!! (note that my post #3 in this thread references yet more threads!)
• How to repair a broken comb flap actuator arm?
• Need help with center console removal on '90 S4

I think there are plenty more threads, too, that you can turn up if you search on things like "center vent clicking", etc.

Since you've got a passenger-side airbag car, you'll probably be needing to use the "make a hole in the air box and operate through it" procedure. See post #3 in the "Weird sound from dash, HVAC ?" thread.


Edit: ahh... I see Rob beat me to it.

Tim968

Thanks Ed & Rob; I will adapt the brilliant write-up from Dwayne's Garage.
I appreciate your help.

Rgds/T