97 century air flow problem in HEAT position

[gandhi001]

For 1997 century (3.1 L), when the temperature setting is on HOT, and, I turn the climate control knob to "HEAT" position (meaning air should flow towards floor), the amount of "air flow" by blower goes down substantially. If I turn it to "DEFROST", without changing the "fan speed setting", there is lot more air flow.
This makes my feet very cold in winter. I replaced one motor, checked all motors, the valves do move. Also replaced the cabin filter. No vacuum leaks either. Still the same problem.
Any ideas/suggestions?

[richtazz]

has the car ever sat for any period of time? IF so, look for a mouse house or other debris in the floor ducts. If it hasn't set around, I'd look to see if the mode valve is fully engaging the floor position.