I found out my problem with the ac/heater blowing out the defrost vent and the floor vent and not the front vents.The problem was under my hood on the driver-side under the hood close to the firewall there is a three way splitter that is which it is a white plastic that has three small air line that goes to the three way splitter check those hoses because they dry rotted and that your vacuum line for your air duct flap mines were rotted and know we back in business.