[Batman]

Well you can eliminate the starter and battery right off the top, neither should be under load with the car running. Not too familiar withthe Opti but it doesn't sound like an ignition problem. Check all your chassis grounds and the connections on your PCM. Possibly one fo the major grounds shorted out. A loose battery terminal shouldn't matter once the car is running unless the alternator is bad. Most likely it is a loos e wire.