What is draining my battery and stopping my car from starting?

My 1991 Buick Regal won't start at times, even though the battery shows that it has power. I wait 30 min. or so, then it will start. Or sometimes the battery is completely drained. It will start when jumped in either case. I have replaced the battery and alternator more than a few times, so that is not the problem.
Monica, June 2005


done
your started needs to be checked

kim, November 2005
Monica -- so many things can drain a battery, and than again there are things that can happen to make you think the battery has been drained but hasnt -- you never said if this happens only from time to time -- every night, after sitting for 12 to 15 hours -- or if it drains sitting for an hour. Or if it wont start when its been driven and its hot??? Lets go with it being a real drain on the battery - Do you have any large amplifier installed in the car for the stereo system -- if you do -- thats the first thing I would disconnect. Do you have an aftermaket radio that is on even when the key is not? That could do it also. If you are mechanical -- what you can do -- and this is only if it happens every night when you park it -- get under the hood -- and remove the positive battery cable -- when you get ready to leave the next day -- hook it up -- see if you can tell the difference of how much power the battery seems to have. If you do this a few days and it seems to take care of the problem -- than you know it is a drain on the system and not some other problem that acts like a drain on the system. If you determine this is the problem than you can take it in and have a alternator or generator shop trace down the problem and fix it -- some of them do great wiring -- some DONT -- same as a regular mechanic - some know how to trace down a problem easy -- some dont. Your probley looking at a 100 minimum. If you want to try it yourself -- since you now know it is a drain -- is find the fuse box and each night -- pull out one fuse -- untill you find the circuit that is causing the problem -- if you find the circuit that is causing the problem -- than you might be able to determine what is on that circuit -- (high beams for instance, and they havent worked for months or years, replace both lights etc,,) and to be honest -- you may never find it this way. Nothing beats a good meter and knowing how to test to find a drain on the wiring system. If you dont have the money -- and worse comes to worse -- if unhooking the battery at night keeps it from going dead -- most autopart stores have what is called a knifeswitch - it attaches to the battery post - make sure you have the right type of battery post -- than your battery wire attaches to the other side of the switch -- so each night you just open the hood -- throw the switch and the battery is now out of the system and you wont have a drain (if you use this -- PUT IT ON THE GROUND WIRE) -- usually these cost 20 to 25 dollars and are made for motorhomes. Each time you will have to reset your clock -- radio stations etc when you disconnect the battery like that. Thats the most help I can give without knowing when and how the battery goes dead. At least its a cheap fix if you do have a drain on the system. David

DavidL, June 2005
link Click here to see other fixes for Regal.