i've always known i had a problem with my a/c since buying the car.. you can hear a clicking every now and again when you turn the a/c on and thats the only time it happens... it blows cool but sometimes it blows hot.. i thought i might have needed a simple recharge.. Its been getting hot here in atlanta lately... 90 degrees today... i was on my was home when i got a strong odor of coolant thru my a/c vents.. when i looked at the temp gauge the car was running extremely hot.. i pulled off for about half hour, opened the hood and let it cool some... it cooled and I continued driving home without my a/c... and the temperature was quite fine with no further problems.. i left it running when i got home and it didnt heat up.. i then turned the ac on and watched the temp rise!!! this is the first time this has happened to me.. im wondering what the problem could be !

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suggestions please