I recently noticed that there is no heat in the cabin when the car is not moving. When I am in motion the heater works fine but if I come up to a traffic light is cools down very quickly. Once I am moving again it heats up fine. I have heard that Subaru uses the coolant to heat the cabin air. I recently had my radiator replaced. Could that be the source of the problem? If so where do I start to look?
Thanks Todd

 

Could be something is constricting the coolant flow, If it doesn't cycle to the heater's core unless you really have the water pump running when on the gas, then something is only partially stopping the flow. Check to see if you have a kinked water hose. It could also be a bad themrostat or blockage in your radiator or heater core. How have your coolant temperatures been according to the gauge on your dash?

jason

 

I noticed that it is running a smidge hotter than normal. i'll check the hoses as you suggested.

 

do the above also you might want to check your water valve and see if its still funtioning corectly. this stops coolant from entering the cabin. yours might be partialy close and when you move pressure pushes coolant past. just a thought.