Not getting heat to the CAB?

I would check the temperature blend door actuator because it sounds like it is not working. Here is the location so you can work the controls to see if the actuator is moving. Also, this guide can help as well. Check the images below.

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

If the temperature actuator is working and if you don't have a coolant leak and there is no milky white appearance in your oil, then the problem is likely with your heating system and not related to the engine.

Here are some things you can check:

Thermostat: The thermostat controls the flow of coolant into the engine and the heating system. If the thermostat is stuck closed, it can prevent the flow of coolant into the heater core, which would prevent heat from entering the cab.

Heater core: The heater core is the component that warms the air before it is delivered into the cab. If the heater core is clogged or has a leak, then the air will not be properly warmed before entering the cab.

Blower motor: The blower motor is responsible for moving the warm air from the heater core into the cab. If the blower motor is not working, then you won't feel any heat in the cab, even if the heater core is functioning properly.

Blend door: The blend door controls the mixture of hot and cold air that enters the cab. If the blend door is broken or stuck, then you may only get cold air or no air at all.

Hoses: Check the hoses that connect the heater core to the engine for any signs of cracks or leaks.

Check out the images (below). Please let us know what you find.