Q: Heater and vent issues

Hello. The symptoms you are describing are commonly associated with a problem with the heater core or blend door actuator. If the heater core is plugged or there is not sufficient coolant flow to the core then the heating capacity of the system may be affected. I would first check to make sure that the cooling system is properly topped off, as low coolant can affect the operation of the heater. If the coolant is good then I would look into the possibility of an obstruction in the cooling system or heater core. These can occur if rust or contaminants build up in the heater core and cause a blockage. Another possibility is that there is an issue with the vehicle’s blend door actuator. The blend door actuator is the component that controls the flow of heated and cool air through the vehicle’s vents. If it fails or has an issue it may not be able to properly direct heated air into your vents, causing your heater to not function. Other possibilities include a faulty thermostat or water pump, though the vehicle will usually experience overheating issues if one of these is the cause. As heating and cooling system issues can sometimes be difficult to diagnose, if you are unsure I would recommend having a professional technician, such as one from YourMechanic, visit your location to diagnose what is causing your heater to malfunction.