Can an bad ignition drain you battery?

Answer 1

While typically an ignition system needs power to operate, there may be underlying circumstance dictating a draw on an automotive battery. If the ignition system is weak, prolonged cranking and a no start condition will enevitably drain the battery. Most modern day automotives are computer controlled systems that provides the grounding of the coil through various inputs. These inputs allow the computer to control things such as spark timing, variable valve timing, injector pulse width, intake manifold runner control etc. A current draw is usually an indication of something stuck on or using excess power as is the case of an electric motor.