Well when i try to start the car it reads on the voltmeter that the battery goes down then as soon as the car starts it goes back up. Also, when i rev the engine too hard it reads on the voltmeter that it goes down and as soon as i let go of the pedal it rises back up. And if i keep on trying to start the car the battery will die out, usually i disconnect the battery just in case the battery does die out when its parked in the backyard but i don't for sure.