NO COLD AIR IN HIGH HUMITY 2009 IMPALA
I am going to recommend something that may or may not help but I think it is worth a try. Get a garden hose and spray nozzle or better yet a pressure washer and clean your A.C condenser coil. My theory is if your condenser coil is in front of your radiator like my vehicle when the fans pull air through the coils fins it's not only pulling air it is also sucking in dirt and bugs that can stick to the fins of the coil and restrict air flow. So if your coil is a little clogged cool air still helps it take the heat out of the freon but when the humidity is high the air is hot not working as well. So if you clean the coil you will get much better air flow across coil and also get better air flow across your radiator since its in back of your coil. Like I said it may or may not work but its worth a try.
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