A/c
 

Last week when it was 99 derees here, my ac decided to give out. It has been blowing cold air without any problems. It would also intermintenly get cold on these hot days. Any suggestions as to what it may be? Is it just because it was so hot that it didn't feel like working?

Need some more information, for starters we need to know if the compressor is in fact running, so do you get an RPM drop when you press the AC button? Can you hear the AC compressor clutch enguaging?

I feel the compressor engage. Like I said, it does work most of the time. It just blew hot air during the heat wave. Also, the blower stopped working unless it was on high. Tried it today and it blew pretty cold and the blower was fine.

Blower stuck on "high" is usually a sign that the resistor pack that controls the fan speed is going out. They can sometimes be repaired.

As for the "sometimes works and sometimes does not," I can think of two things that have happened to me in the past. The first being that the servo motor that controls the air mix flap above the gas pedal was stuck. I took it apart and cleaned it and it has worked ever since. The next item was a faulty climate sampling unit. This is behind the glovebox and connects via a tube to a little grate in the dash next to the lighter. My unit would stop working from time to time and it would default the mixing flap to hot.

In fact the later 944's always seem to default to "hot" when something goes out.