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Q: Air conditioning sometimes cold and then hot

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The air conditioning sometimes is cold and then goes hot. The Freon was replaced a year or so ago.

Hello. When you get an AC system that is constantly changing temperature the most common cause is low refrigerant. If the system was filled within the last year then there may be a small leak that is causing this condition. More commonly on your car though is a failing AC compressor. I have had a lot of these fail on this car and cause fluctuations in pressure which causes exactly what you are seeing. I would typically start with installing a set of pressure gauges to see what is going on in the system. If the pressure is low on both the high and low side then it needs refrigerant via an AC Recharge. If the pressures are fluctuating drastically then it is more than likely the compressor that needs to be replaced.

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