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91 200qw: climate control fan

With the onset of the "cold" weather here in the southeast US, the
climate control  blower has decided to be reluctant to blow at all.  It
is as if the mechanism (sensor?) that prevents it from blowing when the
engine is too cold (the one which is bypassed when the defrost button is
selected) is faulty.  The first sign of the problem was: 1) it took much
longer for the blower to come on if defrost was _not_ selected, and 2)
it would go through the "no blow" cycle even after a short trip in which
the blower was running when the car was shut down.  

I might not suspect anything if I were still up north, but the "low"
temps I'm dealing with here are only in the 30's (dipping to mid 20's at
night, once or twice so far).   At this point, it won't blow at all,
unless I've been out driving for a quite a while, even during daytime
temps of 40-45.

This morning, it worked as it should, i.e. it was 25 degrees, and when I
pressed defrost, it started to blow.  45 minutes later when I ran a
couple of errands, it wouldn't blow at all.  I stopped and started it 3
times, no blower.  Then with the engine was idling, I wiggled the
multi-function thermoswitch connector because the temp gauge was not
giving a reading (another intermittent little bugger), and when I got
back in, the blower was on.  However later at lunch the wire wiggling
didn't seem to help with the blower and the temp gauge was fine.

The temp gauge has acted up for about a year with increasing frequency.
Each time, if it persists, it can be corrected by wiggling the
multi-function thermoswitch connector.

The blower problem is new.  Only once has it seemed to respond to the
wire wiggling method.  

I have suspected the thermoswitch of flakey function for a while now,
due to a boost problem during warmer weather (boost limited to minimal
value after car has been parked not long enough for the engine to cool).
I'm suspecting it even more now.

Is there another separate sensor that is involved in the cold
temp/blower control circuit?  Any other ideas out there?


Ed Kellock ...................... Greenville, SC  USA
91 200qw .......................... 87 Coupe GT