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Q: I poured antifreeze in my car and it's still blowing out cold air when I turn the heater on

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I'm trying to use my heater and I noticed my temperature gauge was more than half so I put antifreeze in it, now it's fluctuating. Why isn't my a/c blowing heat?
Now it's in park and the temperature is at the halfway mark

My car has 110000 miles.
My car has an automatic transmission.

Hello. There are a couple of things to check here. When the antifreeze was added, was the cooling system thoroughly bled (with the heater turned to "Max" heat and fan? There could be air bubbles in the engine or heater core - which don’t transfer heat.

You mention the temperature at the gauge is "fluctuating". A properly working thermostat should keep the temperature steady at the middle of the gauge. It’s also possible your heater control valve is malfunctioning, not allowing hot coolant into the heater core.

I would recommend having an expert inspect the heating system in order to pinpoint the correct repairs for your situation.

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