I fought this problem for three years on my 95 mystique. I finally wired in a manual switch, via a relay, to the fan. The switch is mounted in the dash, so I can turn it on whenever I need cooling, and turn it off the rest of the time. The problem now is to keep my eye on the gauge, and remember to turn it on when it needs it. When summer time arrives, I'll just turn it on and leave it on whenever the car is running.
