Q: Ac compressor turning on and off

asked by on September 14, 2016

My truck was blowing cold air and all of a sudden it would blow only cool and then get back to cold and then sometimes it would blow hot but then the next day it would be cold again. And you can hear the Ac compressor kicking on and off back and forth. I tied adding refrigerant. And I add the correct amount cause it was in the green section and it still cuts on and off

My car has 175000 miles.
My car has an automatic transmission.

Hello. If the compressor is turning on and off fairly quickly then that means that there is still a pressure issue. It can be caused by low refrigerant or high pressure. It can also be caused by a bad A/C pressure switch. Any of these will cause this to occur.

I usually install a set of pressure gauges that will read the high and the low side. If the system is low I add more refrigerant. If the high pressure side it too high then I check and see if the fan is working as it should. If the pressures are fine then there is a pressure switch issue within the system.

If you want to have this repaired, consider YourMechanic, as a certified mechanic can come to your home or office to diagnose the issue with your A/C and help you fix it accordingly.

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