low voltage
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low voltage
My 1985 is dropping the voltage to 11.4 when my a/c is on. When I shut the compressor the voltage goes back to normal. I noticed that the compressor is a little noisy. I replaced the alternator and the battery when I took it to the shop. HELP.
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From: Good health is merely the slowest possible rate at which one can die
St. Jude Donor '04-'05-'06-'07
The noisy compressor is definitely a clue and needs checked further. It or the compressor clutch could be failing causing an excessive current draw. You also need to check alternator output at the alternator and battery and make sure voltage drop between them is not excessive. Check, clean and tighten all cable connections at both ends and also examine cables for corrosion, insulation damage and other signs of age. Check all grounds in the engine compartment. Check the condition of your alternator belt for cracking, glazing and also that the tensioner is in good order. A belt can slip under load but they won't always make noise and so you won't know it. Your shop should have done most of this before they started throwing parts at it. If they didn't, you may want to find another one.
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Originally Posted by Corvette Kid NC
The noisy compressor is definitely a clue and needs checked further. It or the compressor clutch could be failing causing an excessive current draw. You also need to check alternator output at the alternator and battery and make sure voltage drop between them is not excessive. Check, clean and tighten all cable connections at both ends and also examine cables for corrosion, insulation damage and other signs of age. Check all grounds in the engine compartment. Check the condition of your alternator belt for cracking, glazing and also that the tensioner is in good order. A belt can slip under load but they won't always make noise and so you won't know it. Your shop should have done most of this before they started throwing parts at it. If they didn't, you may want to find another one.
