My 2002 Ford Expedition Front Heater blows cold air below 45 MPH. Above 45 MPH the heater works OK. The Rear Heater blow cold air all of the time. Help!

The blend door actuator is located in the left rear quater panel. It's right there when you remove the trim panel (left side rear) Below is a picture of it when panel is removed along with another picture of the air duct system. I also gave you a picture of the connector at the actuator. Make sure you are geting power and test opening and closing. Worst case you could make the blend door stay to where you are geting heat until you can repair the problem...

No hot air is due to low coolant, or even poor coolant flow. The engine heats up the coolant, and it passed through your heater core, and the heater blower motor pushes air through the heater core to warm up the air. If your "fan"is working, but the air is cold, make sure your coolant level is good.

Is the correct type of heater core that use for rear heater?Check fan fix its correct side,or wiring change or return water line is blocked.

Have had the same problem 2000 ford expedition. got it working good now

With your front heat working the most likely cause for the rear heat not to work is that there is an obstruction in the line that is preventing the warm coolant to get to the rear heater core or the rear heater core itself is plugged and not circulating. Another possible cause could be low coolant level where the system has enough coolant to provide the front system with enought warm coolant but not the rear system. Hope this helps

MOST LIKELY ITS PROBABLY YOUR HEATER CORE

its the blend door behind the glove box. I had the same problem

Shelly,

Buy used parts at car-part.com. Look on page with * to find the cheapest part. Coud be your temp blend door (#2) may not be moving back and forth. Or, you are not getting hot water to the rear heater core.


You may have to crawl under the truck and feel the heater hoses to see if they are hot. You will find a group of 4 lines, 2 for heater and 2 for a/c. If hot, you know hot water is getting back to the heater core. If not, there may be a hot water vave that's not working. Not sure if EXP. has a water valve for rear.

Let us know what you you find. Good luck.

check you antifreeze level and make sure its full

impeller is made of plastic on teh water pump and its slipping and spinning on the shaft renew before weather warms up as engine will overheat