This started earlier this spring. I was standing out side my car and could hear the compressor engaging repeatedly. Got in my car and it was blowing warm air until I started driving. My wife drove it without anymore issues for a month. Then it was back to only cooling while driving. Took it to a shop and it passes a leak test but it was a little low on freon, .89lbs to be exact. Afrer charging the system to 1.4lbs the A/C worked great while setting there and on my drive home. The next day l started the car and all I got was warm air. Still only blowing cold air again while driving. I'm going to take it back to the shop and have the same test done and put the freon level put back to 1.21lbs. We over filled it. Could that be it? What do you think?
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Overfilling is just as bad as having low charge.
If ac only works while driving it could be that the condenser is only getting cooled while moving. I would try blowing air at the condenser and note if it cools. If so then check fan operation and/ or dirt on the fins.
