Having problems with your Cars & Trucks ?
My heater is blowing cold air in my 1990 Cadillac Deville
Your heater core may have a blockage. The heater core is like a mini radiator. Rust or electrolysis can cause it to clog. recommend disconnect the two heater lines and blow air threw one line other line have off to the side of vehicle so it will drain into a bucket. If no air goes threw then heater core needs to be replaced. If it is good and air is going threw then flush the engine cooling system.By pass the heater core dont want to send unwanted crap going into the heater core, you can get radiator flush solution at any parts store. Cooling systems need to be flushed every couple of years to avoid corrosion build up and electrolysis use 50/50 mixture when replacing coolant.
Repair Help & Product Troubleshooting for Cars & Trucks
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