No Heat

[Proc]

Hoping someone can point me in the right direction.

I have a v6 (one of 4 mustangs in the family) with no heat coming out any vents. This one has me stumped.

The temperature on the engine is good according to the gauge, coolant level is fine, hoses in and out of the firewall to the heater core are both hot, the blower motor runs just fine on all speeds, the vent selector works as expected sending air out the defrost, footwell, and out the dash, the recirculate vent works (I had the glovebox down and could both feel and hear the airflow change), and the AC turns on an off.

But I have no heat. I can change the dial to max heat but I only get ambient temperature air (it’s cold out, so it is blowing that air at me).

Over time I have changed all four actuators, but it feels like there has to be something else that failed.

Google is no help because everything that comes up has to do with the actuators.

 

[LikeabossTM]

Sounds like a plugged heater core

 

[Proc]

Isn’t there something that controls the airflow to go to the heater core vs the AC evaporator coil?

 

[Proc]

Well, I flushed out the heater core. It was clean and blasting air flowed both ways with no obstructions and no gunk. No change in the interior temp.
The metal piping leading to and from the heater core hoses get hot to the touch (one is cooler than the other).
Engine gets up to operating temperature, coolant level is good. I’ve done the 4 actuators. Any other thoughts?

Could the temp switch in the center cluster be bad?

 

[86GT351]

Sounds like the Temperature Blend door actuator might be bad or the attachment to the air box might be broken

 

[2008_ScarlettGT]

Just a shot in the dark, but on my dads explorer the radiator cap went bad and wasn’t holding pressure and caused him to not have heat. Something minor to check if you haven’t already.

 

[Proc]

Btw, closing this out, it was the temperature blend door actuator.

I was being a dummy and forgot that one is different than all the rest. And I was being stubborn thinking “it can’t be that! I replaced it once already!” Swapped out the old one (it lasted a whole 16 months) and all was good.

Thanks all!

 

[JC SSP]

Sounds like the Temperature Blend door actuator might be bad or the attachment to the air box might be broken

View attachment 85597

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