Heater not working on 2002 mercury sable gs - 2002 Mercury Sable

Okay, switch to hot on temp control, warm up car to normal operating temp. You will see at the firewall a couple of heater hoses but only 2 go in the firewall to inside of the vehicle. Be careful because of engine hot and moving belt. Reach down probably with your left hand and touch one hose at a time. Most likely 1 hose will be hot to touch and the other will be cold or cool. If there is a big difference then your heater core is clogged and needs replacement. Very expensive repair $800 Okay, switch to hot on temp control, warm up car to normal operating temp. You will see at the firewall a couple of heater hoses but only 2 go in the firewall to inside of the vehicle. Be careful because of engine hot and moving belt. Reach down probably with your left hand and touch one hose at a time. Most likely 1 hose will be hot to touch and the other will be cold or cool. If there is a big difference then your heater core is clogged and needs replacement. Very expensive repair $800

How about the heater control valve in that be bad or it's not getting back in How about the heater control valve in that be bad or it's not getting back in

If air is blowing but not hot it's not the motor as someone just wrote it's probably a stuck temperature blend door and or actuator , good luck hope I helped If air is blowing but not hot it's not the motor as someone just wrote it's probably a stuck temperature blend door and or actuator , good luck hope I helped