Q: Coolant leak causes smoke, periodic abnormal engine temp, and no heat inside.

Hi there. Look all over the cooling system for any coolant leaks. When the engine smokes in the mornings, look to see where the smoke is coming from. If a core plug (freeze plug) is leaking, then the coolant will drain onto the exhaust pipe making the coolant burn off. Check the water pump for any leaks. Check the heater hoses, radiator hoses, and radiator for any leaks. If there is no leaks and the coolant is low, then check the engine oil and see if the engine oil is milky. If the engine oil is not milky, then check the transmission oil and see if its milky. If the transmission oil is milky, then the radiator is split and causing the coolant to transfer into the cooling part for the transmission. If the engine oil is milky, then either the intake gasket is split or the engine has a burned head gasket. For the heater to not blow warm air, check the heater control valve and see if the coolant on the heater hoses are flowing. If both the before and after heater hoses to the heater control valve are the same temperature, then the heater control valve is working and the heater core may be plugged up. If the coolant hoses are different temperatures, then the heater control valve is not working and would need replaced. I recommend seeking out a professional, such as one from Your Mechanic, to help you with your coolant being low.