Blend door actuator?

If you look under the hood (firewall), you will see where the heater hoses attach on the firewall. They attach to the heater core. It is on the inside of the vehicle where the hoses attach.

Let me know if you find it.

I need you to check something. With the engine at operating temp and the heater on, do both heater core hoses get hot?

The only thing left is the blend air door. It must not be opening toward the heater core. If the heater core hoses are hot, then the core must be hot. Something is stopping the air from passing over it. That would be the blend air door. That is all that is left.

Try checking it one more time.

Let me know.
Joe