Heat not working

Hello,

There are few reasons for the heater to blow cold air. It could be due to low on coolant, as low coolant will have insufficient flow thru the heater core.
It can also be due to a clogged heater core, which will lead to low/no flow of coolant in the heater core.
Also, if the thermostat is stuck open it will not allow the engine to warm up sufficiently and the heater will blow cool air.

One of the common causes besides these is a faulty blend door actuator. The blend door actuator controls the hot to cold and cold to hot flow of air.

https://www.2carpros.com/articles/replace-blend-door-motor

Take a look at this article it covers the typical no heat issues:

https://www.2carpros.com/articles/car-heater-not-working

Please let me know of any questions.
Thank you.

Hi,

The first thing I suggest is to simply check the coolant level. If it is low, fill it to see if that makes a difference.

Next, turn the heater on and allow the engine to reach operating temperature. Turn the engine off and feel both heater core hoses under the hood at the firewall. Both should be hot. If one is and the other isn't, suspect a plugged heater core. Here is a link that explains how to flush the cooling system. When doing this, remove both heater core hoses and spray water through each direction until the water runs clear. Simply use a garden hose for this.

https://www.2carpros.com/articles/coolant-flush-and-refill-all-cars

Now, if both hoses are hot, chances are the blend air door is inoperative. The blend air door is what controls the air temperature entering the cab. When they go bad, what you are experiencing is usually what happens. Oftentimes, you will hear a clicking sound under the dash when it is trying to adjust.

The blend air door actuator is located in the passenger compartment of the vehicle, on the front of the heater case, under dash. See pic 1.

What I suggest is to remove it. Once out, plug it into the wiring and change the temperature from cold to hot and opposite to see if it reacts. There are small plastic gears that break and often make a clicking sound when they fail.

Pics 3 and 4 below are the directions for removal and installation. Use this to remove for inspection.

I hope this helps. Let me know what you find or if you have other questions.

Take care,

Joe

See pics below.