[V8] Heater plenum puzzle

[cobram at juno.com]

It's been a VERY long time since I've been into a heater box, but that
might be the feed for the vacuum actuator valve for the heater box.  Some
models had it, I've seen plenty where it was just tossed when bad and a
longer heater hose was used.
Could have been the case here.  Some models had it, some didn't, maybe
that box is a replacement out of a car which didn't have it?  

When the valve got stuck on the 200TQA,  I ordered new hose too, which I
would have had to cut to install the valve, so I just left it out, one
less thing to break.

Can't be positive though, as I said it was long ago, but I have a vague
recollection of that plastic hose being hooked up when I did the 200TQA,
and not being there at all on the '90 V8Q.

BCNU,
Experience is the name everyone gives to their mistakes

On Thu, 10 Oct 2013 20:34:30 +0300 =?iso-8859-1?Q?Ari_Palom=E4ki?=
<ari.palomaki at pp1.inet.fi> writes:
> Eh, I think I found the answer - that tube is not supposed to be 
> attached to
> anything, it probably acts only as a ventilation tube for the metal 
> box, in
> which the stepper motor resides. I opened the box and found it is 
> actually
> not connected to anything at that end either. I guess it is routed 
> to cabin
> to ensure it does not draw moisture or even water inside the box.
> 
> So, live and learn...
> 
> -Ari- 
> 
> 
> 
> -----Alkuperäinen viesti-----
> Lähettäjä: v8-bounces at audifans.com [mailto:v8-bounces at audifans.com] 
> Puolesta
> Ari Palomäki
> Lähetetty: 9. lokakuuta 2013 20:33
> Vastaanottaja: 'v8audi fan'
> Aihe: [V8] Heater plenum puzzle
> 
> Hi all,
> 
>  
> 
> I am in the middle of replacing heater core and blower motor on a 
> ’92 model
> with later airco(flaps operated by stepper motors instead of vacuum 
> servos)
> and could use some inspiring ideas.
> 
>  
> 
> While removing the plenum, a white-colored plastic tubing, which 
> goes thru
> the plenum housing,  came loose from somewhere in the upper parts of 
> cabin
> side and I am a bit puzzled where it should go – that area is pretty 
> tightly
> packed with air ducts and I cannot see or feel anything up there. 
> The tube
> position and direction in the plenum implies it connects to
> something(probably to a piece of rubber hose) in the upper area 
> somewhere
> close to cabin temperature sensor(although the sensor should not 
> need this).
> The other end of the tube connects to a stepper motor, which 
> controls the
> round flap in the evaporator. I have not removed dashboard skin yet, 
> but may
> have to do so...  
> 
>  
> 
> Does anyone have a “touch” to this – for clarification, please take 
> a look
> at the image – http://www.flickr.com/photos/ap_shared/10172569245/
> 
>  
> 
> Thank you for your time,
> 
> -Ari-
> 
> Finland

.