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Q: Charging system failure.

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Battery gauge goes almost to red. Check Guage light comes on. Battery acid is coming out. Replaced alternator and battery. Still overcharging. But not all the time

My car has 306463 miles.
My car has an automatic transmission.

Hi There, You may have a failing voltage regulator that could be allowing the alternator to supply too much or too little amperage to the battery resulting in the battery never maintaining a consistent charge as it is designed to. The voltage regulator is a unit that regulates the charging of the battery by the alternator. When the voltage regulator is not working properly, this may result in the alternator allowing too much power to be delivered to the battery resulting in damaging wires and prematurely sometimes destroying the battery. A common sign of this is usually the acid inside the battery boiling causing the battery to swell or leak acid out as you have described. I would recommend having an expert from YourMechanic come to your location to diagnose and inspect your charging system.

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