1995 Bonneville, AC and heater only blow through the floor vent and defrost vents, not the middle ones.
03 Pontiac vibe / heater blows cold air when driven slowly (or at idle) even when motor is up to normal temp. Blows hot air when driven on the highway. Temp gage worms up normal. Makes me think thermostat is OK.??? Doesn’t leak antifreeze. Heater core, bad circulation???