Q: Car is overheating and no heat. 2000 Dodge Neon

Hi there - you may have 2 distinct problems at this point. If your engine is still overheating, the cooling system may not have been bled properly, leaving air pockets in the system, and causing poor heat transfer, no heater function, and overheating. It’s also possible you have a blown head gasket which is causing excessive pressure in the cooling system as well as overheating. The lack of heater function may be a failed or malfunctioning heater control valve, which lets hot coolant flow into the heater core to provide passenger heat. I would recommend a cooling system inspection by a mobile, professional mechanic, such as one from YourMechanic, who will come to your location, diagnose this problem, give you an accurate assessment of damage and cost estimate for repairs.