Freestar owners...is your A/C system functioning ok?

I have a problem with the 'recirculating inside air' function. It stays on for 12 minutes then lets in smelly outside air. All my other vehicles never did this. I could breathe fresh inside air as long as I wanted. Dealer doesn't think it is a problem...won't correct it. Also, I have to press the little 'car' button to get it to come on inside air. Manual states it should come on automatically in auto mode, but it never does. I need other owner's experience to know if the car was designed this way (huge oversight) or some of us have faulty systems. thanks!

in auto mode, a certian set of parameters would have to be met... would be interesting to see what they are; sun load, ambient temperature, in-car temperature, etc...