Re: 1997 A/C is intermitant...help requested.

I have a 1997 GMC Sierra with 350. I can go out and crank it up and

>the AC will blow ice cold, for a long as I am moving or do not shut >either the AC or the engine off. If I shut it off an then turn it on >again the AC will blow warm air and get progressively hotter. It does >not matter if I only drive 1 mile or 100 miles. I thought it may be >freezing up, but it was not. I thought it may be a bit low on freon, >so I bought a recharghe cyclier of freon, but then I noticed when this >sudden stoppagage of cold air occurs the compresser is not turning. I >figured its got to be low on freon and the pressure switch is keeping >it from running. I wait and catch the system when it is working and >hook up the charge cylinder and gage, but the system shows sufficient >freon, so that should eliminate low freon as a problem. > >When it does work its good and cold. I am at a loss.any ideas what to >look for? Possibly a clogged dryer? Vehicle only has 50K on it. Taking >it to a dealer is out of the question for now. >Regards
Reply to
Mike Levy
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I just got finished with playing with this system. I too have come to the conclusion its the pressure switch. I can start up the AC watch the clutch on the compressor kick in, and everything works. Then it will click off, and just a jiggle of the plug on the LP cutoff switch is enough to get it going again. I also used a jumper and it will just keep runnning and running and running. Compressor etc all sound fine, but I did manage to add a small amount of freon, hope tht does not hurt anythng, but its getting super cold now, just like when new. MAybe it was a bit low, but I do honestly thnk its that switch on the accumulator.

Thanks for your input Regards

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foundry and general metal working and lots of related projects.Regards Roy aka Chipmaker // Foxeye Opinions are strictly those of my wife....I have had no input whatsoever. Remove capital A from chipmAkr for correct email address

Reply to
Roy Hauer

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