91 Air Conditioning Does not blow cold
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Joined: Dec 1999
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From: Harrison Twp MI
91 Air Conditioning Does not blow cold
Our 91's air conditioning stopped today. The light above the AUTO button was flashing. The book indicates this is an electrical problem or the freon is low.
I read that when the freon is low, a switch turns off the compressor. I don't hear the compression going on when I activite the air.
Given this does it sound like a recharge or possibly an electrical problem?
Thanks,
Jeff, hot in Michigan...but its raining today so no vetting anyway.
I read that when the freon is low, a switch turns off the compressor. I don't hear the compression going on when I activite the air.
Given this does it sound like a recharge or possibly an electrical problem?
Thanks,
Jeff, hot in Michigan...but its raining today so no vetting anyway.
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Joined: Dec 2000
Posts: 7,839
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From: San Diego, Ca
Re: 91 Air Conditioning Does not blow cold (jgrice)
Most of the switches are fairly reliable and if you have the low charge code, you need to find the leak and recharge it. Most GM's leak at the evaporator or compressor shaft seal. If it's the compressor shaft seal, there will be an oil stain on the hood above the compressor. Remove the oil as soon as possible as there have been some posts about it weeping through the laminate and destroying the paint (if not the hood). The evaporator is encased, so the best way to determine if it's leaking is to go to an a/c shop and have them stick an electronic tester in one of the vents. Of course the a/c has to be working for the tester to work, so an a/c shop might have to add a lb to get the compressor going. Other signs of an evaporator leak would be frost on the windshield - freon is about 22 below at atmospheric pressure, so ice forms rather quickly. Other spots that leak, are all fittings and where the switches attach to the lines - look for oil & grime. If a fitting is leaking, probably time for new o-rings.
