AH06GrandPrix
New member
Base model car 2006 gp. the last few winters it does not blow much heat. I had the heater core replaced last March, when it went bad. I put a new 195 tstat in it this summer, no fix. If I reverse the hoses going to the heater core it blows more heat, then just after a couple days goes back to very little heat again.. I keep checking the coolant level, seems to be full.. I have bled the system from the top of the tstat housing. How do I check to see if the water pump is circulating properly? Any other ideas? Thanks