What should a good battery give for a voltage reading ??? Mine has been sitting for about 2-3 days and has been sitting at 11.8 volts is this still considered a good battery or is it time for a new one ??? Not sure how old this one is since I've owned the car for less than a year now. Just want to find out what a good one should read. When the car is running it reads 13.8 to 14.1 of course I am battling with a possibly bad alternator and am not sure if this battery is bad and caused the alternator to go bad or what. It is a pain in the butt to remove the battery so I do not want to take it out of the car to have the part store check it if I do not have to. As always thanks in advance for any help you can give. :seeya

 

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You have normal voltage for a good alternator. As batteries age, their amp hour capacity reduces, so it is possible that your battery voltage could fall into the discharged battery range (less than 12.0 volts) after sitting for a couple days. Also, you could have high leakage current and you can measure this current by putting your VOM on amps and disconnecting the neg cable and placing your ammeter in series with the battery terminal and the cable. Start your ammeter out on its highest scale, or touch the ammeter leads together (while connected to the batt and cable) until the courtesy lights go out (they draw a couple amps). When the courtesy lamps go out, switch your ammeter to lower full scale until you can read the current. It should read under 50 ma. My 87 measures 28 ma. If you have normal leakage current , then I would suspect an aged battery. If you have no trouble starting after sitting for a few days, I wouldn't worry, but winter starting current requirements are higher than warm weather and you might get stranded one fine cold day. Batteries are cheaper than getting stuck somewhere IMHO.