What actuator would cause my dash vents not to blow air

This would be the mode door actuator.

Thank you for getting back with me.
Where are those located?

Hello,

Here is a guide to help walk you through the steps of replacing the mode actuator with diagrams below to show you how on your car:

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

I have included all blend door actuator locations so you can see how the system works. Check out the diagrams (below). Please let us know if you need anything else to get the problem fixed.