Hi, new to the forum, love it!

Since the 2nd winter until now of having the car, I have had heating problems in the winter months. I have had GM check and change the thermostat as well as do a pressure check on the system, nothing really changed.

I'm in Edmonton, when its <-15C the car will come up to temperature on the gauge and I will get warm air, not hot. But if I stop at a light, the engine temp will drop. To me, this is a classic sign of an open thermostat. Is there something I am missing?

I also put cardboard in front of my rad to help keep it warm.

Does Chev make a low temp thermostat that is harder to open? Any suggestions would be greatly appreciated.

Thanks