Q: Problem with battery discharging over a couple of hours. Alternator getting hot while running very quickly.

asked by on September 29, 2016

just bought car a couple of days ago,ran fine washed it,cleaned engine,noticed when i stated it and let it run,tuned rear wiper on,and it wouldnt turn off.i pulled fuse for rear wiper and left it out.wife cleaned carpets and in that time battery went dead about 1.5 hrs.so i jumped it let it run,took it for about a 45 min, drive.shut it off, restarted just fine.next morning it was dead, this has happened 4 times,i noticed that alternator gets hot while running pretty quickly. i have a charger that checks the alt,and also the battery separately both came back good, there is a porcelain resister on passenger fender well also getting hot.please help me figure this out,wife needs car for work,im off of work from injury and low on finances. thank you so much

My car has 215000 miles.
My car has an automatic transmission.

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This may be related to a voltage regulator malfunction. This is the resister on the passenger fender well that you are referring to. This is a device that monitors the charging system to be sure the battery is charged at the rate and voltage that it should be. When this is not functioning correctly, this will cause the battery to die intermittently which can also cause the alternator to work harder than normal as well. I would recommend having an expert from YourMechanic diagnose the charging system issue in person to verify the problem and proceed with the proper repair.

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