i think its the alternator


Founding Member
Jun 16, 2002
Danbury, CT
My car starts sometimes... most of the time actually, but the battery gets so low after driving it long enough for it to warm up that it wont start again in most cases. I can pop start it though and it will run, but it did stall once last night and not start again. At that time the battery was so low i couldnt even hear my very loud fuel pump. Is that my alternator going to sh**? or could there be something else?
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that sound like the alternator to me, unless you have a wiring problem, which i doubt (if the alternator wiring is faulty, it may not be charging you battery properly).

If you have a voltmeter, check battery voltage with car off (should be 12.5V), then check again with car running (should be 14V +). If you don't have a voltmeter your dash gauge will give you some indication. if the voltage appears low (below the half way point), then the alternator is not working properly.

If you have a stock alternator, you can purchase a re-build kit for around $20 - and its simple to do. the re-build kit comes with new brushes (which it problably the problem with your alternator, and it also coes with a new voltage regulator) the brushes are 2 rectangular pieces of soft metal which rub against the spinning rotor and produce electricty. these brushes will wear completly down within 5-10 years. You can buy and replace just the brushes, which cost around $3.
the battery is maybe 2 years old and hasnt been in a car the whole time, but it has been recently for about 4 months. I unbolted the battery and ran the car cold for a few minutes, so it cant be the alternator or the car would have died right? I dont think its the battery either because the lights are fine, and the car starts unless it has been driven for a while. Could running the car drain the battery? and if so, why would it recharge itself with the car off?