Out of no where, my heat decided to go out the other day.. I replaced the thermostat and did a coolant flush on it yesterday thinking that may be the problem since the thermostat was stuck wide open.. Well, this did not fix anything.. The air coming out of the vents is still ice cold, even when I have the heat on pulling it off the engine. Im confused now and were getting down to the low 20's at night and having a high of mid 30s during the day.. any help would be appreciated as this is my daily driver for the time being