Automotive/What should the low side pressure be?

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Comment	Very welcome response, and to answer his questions, I use my old set of refrigeration gauges. Based on his feedback I have a little too much R12 in my truck. I have seen many people add it until the fitting near the compressor gets ice cold, but mine is still quite warm, but I definately added more than it takes to get all the bubbles out of the window. I also noticed that the vent output temperature is now about 40degrees, and before it was regularly 20 degrees when the temp outside wasn't hot. I thought I needed to add a bit more because the truck takes 15 minutes on the freeway to cool down on a hot day and that seemed excessive. I also noticed that the compressor disengauges at a low idle speed, which I also though might be related to a low charge, but adding more made no difference. I raised the idle a little so it no longer goes low enough to stop the compressor,but that's a mickey mouse fix. I suspect there is something like a vacuum switch that is opening when the idle gets low enough. Thanks, and if you have more ideas that might help me, I do apprechiate the help.



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Sean Halliday

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general auto repair,japanese,bmw,mercedes,mini cooper 1960/2009,general british cars,ford.I DO NOT work on automatic transmissions.Manual transissions i install clutches only.Many people ask me to diagnose noises from their cars,unfortunately i cannot do this unless i hear it.As you appreciate,vehicles can and will make a variety of noises.I DONT UPGRADE or fit aftermarket performace kits,parts,chips,only replacement parts.

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40 years experience on all general auto repair.

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