I have a 2003 ford winstar and i'm having problem with the front heater. It blows cold air , the rear one works fine. What could it be?

Well the first thing I would want to know is if the rear heater core is getting hot.
You can check the heater hoses if they are accessable, or pull the cover off the unit next to the third row seat and check the core.

Most likely the blend door actuator. Do you hear clicking behind the dash? If so that's the problem. Excellent video on youtube goes throught the whole process, about 30- 40 mins to fix.

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

Check the operation of the temperature control door. It is located in the center of the dash behind the radio. Look up between the gas pedal and heater case. It is white in color Move the temp knob while watching the actuator. If it is clicking it is bad. Good luck.

sounds to me like you have a rear temperature door motor not working, remove rear left side panel to gain access to the heater box. and it will be the top acctuator twards the rear sells at dealer for @ 60-70 bucks

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

Temp. actuator maybe. A electrica motor that moves a door from cold to hot in the rear HVAC unit . Removing the rear trim panel to get at the auxiliary HVAC unit would need to be done . Search on youtube , video showing how to do it .
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You either have a bad control, or motor running the air direction door in the front HVAC unit, or a door that is stuck.

The front and rear units are totally separate.

The door directs where the air, cold or hot, should come out, whether it is panel vents, floor, defrost, or any combination of those.

This door and motor are located inside the heater box which usually requires a lot of the vehicle dash assembly to be taken apart to get to these parts.