Re: coolant temp sensor breaks AC?

[dwall@sisna.com]

I had a Lumina Van a couple of years ago that, after having the air 
conditioning recharged, would work for one day then stop cooling.  The air 
conditioning repair shop checked it for leaks over and over, but 
everything seemed fine.  Eventually determined that the switch which was 
supposed to turn the cooling fan on when the AC is turned on (proper name 
for this switch escapes me now) was bad, which was causing the compressor 
to basically dump the freon over the bypass valve.  You might want to get 
the coolant temp sensor circuit functioning properly, as this might be 
causing the same type of problem in your system, although I'm not sure 
about how the 90Q system is wired.

Darren D. Wall
darrenwall@netzero.net
dwall@sisna.com
1985 Audi 4000 Quattro
1969 911 Turbo-Look 2.7Liter
1984 Volkswagen Vanagon (The Bus)
1999 Nissan Quest (The Wifes Kid Hauler)


Greetings,

The AC in my 90Q 20V stopped working (noticed it today) and it had been
working 2 weeks ago.  The fan seems to blow (not very strongly); however,
cold air does not come out.  I should mention that 1.5 years ago, I
had it recharged: refilled with freon, etc.  My mechanic told me then that
there weren't any leaks and everything looked great.  I ran the 
diagnostics
and it told me that the "Coolant Temp Sensor has an open circuit."  Okay,
so, this has come unconnected or is broken.  Would this prevent it from
cooling?  The compressor DOES cycle (according to the diags).

I did two things to the car after the last known time it was working and
before this: 1) Install a K&N Air Filter  2) Hose down the engine area
because there was a lot of crap built up over the winter...

In performing either of these, could I have loosened (or broken) the temp
sensor?  Is the temp sensor the reason for my troubles?  If so, where 
would 
I begin to look for the piece?

Any help is greatly appreciated!

Sincerely,
Brian

'90 90Q 20V
'96 A4 2.8Q