[Es2] [audi20v] Re: '91 CQ HVAC Box Sealing & Dash removal

Peter Schulz pcschulz at comcast.net
Thu Jun 12 06:19:44 PDT 2008

Chris, Bernie...

I followed Bernie's advice on this about 5 years ago.
There's a vacuum distribution block under the dash on the driver's 
side, right against the airbox.
There is a white vacuum line entering the block from the Climate 
Control vacuum controller, and it has a plug on the opposite side.

Remove the plug, then run the vacuum line from there through the 
firewall grommet of your choice to the engine side of the firewall.
You may have to cut a bit of the heater hose on the engine side to 
make room for the type 44 heater valve. Connect the heater valve 
vacuum nipple to the vacuum hose you installed, connect the 
electrical lead to the temp sensor in the heater valve and you should 
be good to go.

I used some scrap green rigid vacuum hose from the locking system and 
a short section of rubber vacuum line to connect the heater nipple to 
the rigid vacuum line.

No the Climate Control head will signal the vacuum controller to 
automatically turn the heater valve on and off.

The only downside to this modification is that if the flap controller 
motor is inoperative or not working correctly, it make not allow you 
maximum heat when the CC head calls for it....

The whole process should take less than an hour, but if you have 
large hands and frame it may take longer to work in the confined 
under dash space...

Definitely a modification that I will do when removing the dash for 
the eS2 conversion on the Coupe...


At 05:56 AM 6/12/2008 -0700, Bernie Benz wrote:
>I think that the 200 valve is a NO valve, requiring vac to close. The
>controller probably has the correct vac output for such a valve,
>plugged at the first connector block. Think I posted about this 10
>years ago.
>On Jun 12, 2008, at 4:42 AM, Christopher Gharibo wrote:
>>Instead of messing with degrading foam restoration, what is your
>>opinion on
>>stopping the coolant flow with a heater control valve from let s
>>say a '91 200
>>and splicing it into the heater core feed line (drivers side hose)?

-Peter Schulz
Chelmsford Ma, USA

1995.5 S6 Avant Emerald/Ecru
1995.5 S6 Avant Silver/Platinum
1991 200 20v Q Avant Titan Grey (for sale)
1991 90 20v Q Red
1991 CQ silver  (eS2 recipient) 

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