Ford Repair: Air conditioning 2001 Ford Taurus, ford taurus, ac controls

Question
I have a 2001 Ford Taurus.  The air is blowing and goes from warm to cold then warm and then cold again.  Could this be as simple as adding refrigerant?  If so, what type of refrigerant should I put in it? I purchased 134a, but now I'm not sure that's the correct one! Thanks!

Answer
R-134 has been in use in new vehicles since around 1993. Do not add refrigerant without knowing if the system needs it or not. The only method to know for sure is by hooking up pressure gauges.

You may have a problem in the blend door area, Fords are common for breakage or motor failure in this area, which generally causes a loss of temp control.

Does this Taurus have Automatic AC controls or manual?