Might be tough to do, but where the two lines go thru the firewall, join them together with a tube and clamps.
where is the heater control valve
location of heater control valve on 2005 mercury marguis ?
take it to the dealer
This is not easy. Get a manual on your car from DISCOUNTAUTOREPAIRMANUALS.COM
You must remove the dash.
I believe you are looking for blend door actuator???
heater core is leaking.
You are likely in an antarctic region.
take it to a shop
Heater core leaking.
The heater core is behind the dash the passenger side of the car.
Check to insure that the engine coolant is full and the thermostat is not stuck. Without the heated fluid from the engine the heater will always blow cold air.