I have a 1977 280z, I have replaced the alternator, and voltage regulator but for some reason my battery keeps dieing? I have gone through 2 voltage regulators at auto zone now and they are both reading my alternator is good but my regulator is bad. The guy there said that is impossible that we gave you two voltage regulators one after the other that were bad. Has anyone had this battery draining problem before? Yes the battery is a good battery, its already been tested. I have checked all grounds and they seem fine as well.