Q: Charging 14 volts and drops to 11 volts then back and forth

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Ford 302 c.u. carbureted with a fairly new alternator and a blaster 2 coil. The car will start and is charging 14 volts then for no apparent reason will drop to 11 volts then back up to 14 volts. I thought it may be a faulty gauge but when I take it out at night when it drops down to 11 volts the lights begins to fade. Then when it goes back to 14 volts the lights go bright. I've checked the connections at the alternator and the coil. Any suggestions?

This is most likely caused by a poor connection to the voltage regulator or the alternator. Try to lightly wiggle the alternator wires all the way from the battery to the alternator and regulator connections to see if you can get the voltage to jump when a connection is moved. If none of this works then you may have a defective alternator with a loose solder joint inside it. If you need help with this, a technician from YourMechanic can come to your car’s location to pinpoint the voltage issue and let you know what repairs are appropriate.

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