How do you bleed the coolant system? i am having the same problem

Ok, that clarifies what the problem actually is. You need to run the vehicle with the radiator cap off so you can add fluid as needed. The vehicle needs to warm up so the Thermostat will open. Until that opens there is no water flowing. Now, once it is warmed up you can release the clamp on the lower radiator hose that goes into the firewall so that it leaks a little and allow the air bubble to be pushed through. Now it may not be an air bubble problem. On the upper line going to the Firewall and Radiator core there is a control valve that has to open to allow the water to flow into the core from the engine. Before you start the bleeding process test that with a vacuum pump, it is normally vacuum operated. Make sure it is open or no matter how hard you try your never going to get hot water to that core. If it is sticking or not opening replace that. If it functions with a Vacuum pump but doesn't function when you have the Temperature select set to heat then you have another problem somewhere in the controller or motor interfering with that vacuum. Also, if you select Defrost, the AC compressor activates as well which will cause the system to cool from the AC system. Ok, that clarifies what the problem actually is. You need to run the vehicle with the radiator cap off so you can add fluid as needed. The vehicle needs to warm up so the Thermostat will open. Until that opens there is no water flowing. Now, once it is warmed up you can release the clamp on the lower radiator hose that goes into the firewall so that it leaks a little and allow the air bubble to be pushed through. Now it may not be an air bubble problem. On the upper line going to the Firewall and Radiator core there is a control valve that has to open to allow the water to flow into the core from the engine. Before you start the bleeding process test that with a vacuum pump, it is normally vacuum operated. Make sure it is open or no matter how hard you try your never going to get hot water to that core. If it is sticking or not opening replace that. If it functions with a Vacuum pump but doesn't function when you have the Temperature select set to heat then you have another problem somewhere in the controller or motor interfering with that vacuum. Also, if you select Defrost, the AC compressor activates as well which will cause the system to cool from the AC system.