95 Oldsmobile not charging enough volts I put new alternator starter on charging 13.6 to 14.0 eventually running down new battery old aternator did samething auto zone tested aternator tested good?

Answer 1

Did you have them re-test the battery? It could be a bad battery again, even thou its new. They do come faulty, even when new. If that doesnt correct it, you could have a bad charging wire (the large wire that goes from your alternator, to your battery). Or you could have a short somewhere in your car, which would mean a trip to the dealer in my humble opinion.

Answer 2

A battery needs to be fully charged to get an accurate reading of the charging system. With a fully charged battery and engine off, you should have a reading of 12.68 volts (min of 12.5 volts) at the battery posts. With engine running at idle and no loads, you should have between 13.5 and 14.5 not to exceed 15.5 volts at the battery posts. With engine running at aprox 1800 RPMs turn on wipers, AC, headlights, etc. you should have no less than 13 volts at battery posts. If the system passes all this you may have parasitic draw. This happens when something is drawing the battery down such as a glove compartment light, trunk light or hood light staying on. A max parasitic draw of .050 mA is allowed. Any more than that could lead to a run down battery.