So, it seems I have little to no heat in my car, it’s been double digits below zero all week, so this is perfect timing for it. It’s never had particularly good heat, but now it is just useless. It will eventually defrost the windshield, but it will never get comfortable in the cabin. The only thing making my 40 minute commute bearable is the heated seats.

The coolant temp needle never breaks 175, and I was able to confirm this with the Torque app on my phone. I have had the coolant flushed in the past, and this past fall I had to replace the coolant elbows and drained the system to do that. I have verified the mix is good, so no issues there. The blend door seems Ok, as I had the ability to switch between heat and cool during the fall months. Anyone have any ideas?

The car is a 2005 Monte Carlo with the 3800 Series 2 V6

Edit - Thanks all, I will try a new thermostat first and see if that takes care of things.