2002 Ford Taurus Wagon - 55K miles–Occasionally will experience cooling failure when temperature control is set for cooling. Sometimes it works and sometimes it doesn't. When it's not delivering cool air the clutchis engagingproperly and suction line is cold but air delivered is room temperature. Switching temperature control to heating will reliably deliver hot air. Any suggestions?

 

I have a 2000 Ford Taurus Wagon SE and had the same experience, Here is what I did: There is a Drain Port located by the Firewall on the Passenger side of the Vehicle behind the engine, down by Exhaust,this allows the Heater Core to drain properly when using the A/C. This sometimes gets clogged, and needs to be cleaned.

I also had the System re fridged with coolant. this may help allot.