Nope. Something is not charging correctly or there is a short. What does your voltmeter say when it's running?(it should be about 2/3-3/4 the way to the top line) If you have a dead short in your lights or similar, it can suck a good amount of amps off of your entire system.
In my truck, for instance, when I start it, I have to turn the radio and lights off first or else the thing sucks too much juice and the starter relay won't trip more than half of the time.
