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Why would the car overheat but no hot air come from the heater?

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βˆ™ 2015-07-14 15:05:21

Best Answer

You didnt say if the water pump was changed. No hot air means no circulation.

AnswerBrittany, You have 2 symptoms of a larger problem. It is like you said "I have a terrible headache and black eye." What happened was you missed the ball and it cracked you in the head.

Anyways, Coolant is a fluid that keeps a car from getting too hot among other things. If there is low coolant the car will overheat. When the coolant ciculates through the engine it will also go through a thing in the dash that is like a small radiator called a heater core. A fan or blower move air through this part and pushes the hot air from the heater core into the passenger compartment. This heater core is usually the highest point of the coolant flow. Since fluid seeks it's lowest level, the heater core is the first to lose the hot coolant. Therefore your blower blows accross a cold heater core and gives you cold air.

If you don't have a leak, then when the thermostat was replaced, the coolant may have not been bled of the air in the system.

I would first fill the coolant and check for any leaks first. There is a common problem with the Buick centuries if you have a 3.1 motor. The intake manifold gasket is common for leaking.

In any event, don't run the engine if it goes into the red. Overheating can cause headgasket problems. See othe posts regarding this issue.

Let me know how you make out.

AnswerGlad to hear your problem was resolved.

The heater core does not need to be removed to be checked. If the hose going into the heater core is hot and the one coming out is cold, the tells you it is retricted. Another way to verify is to remove the hoses going to the core, hook up one without installing into the car and run it. It should get hot-very hot, and then see how hot the hose is coming out of the core is like now.

AnswerIf this person that replaced the thermostat put it in backwards this could cause the car to overheat and the heater not to get hot. EzForJesus AnswerSimple - It is low on radiator fluid (water or anit-freeze).
2015-07-14 15:05:21
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Q: Why would the car overheat but no hot air come from the heater?
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