My '93 ES300 runs like a top, but I notice that when I put the car in neutral, the power seems to dip a bit. Not a lot, but it's noticeable. The headlights get just a little dimmer, the HVAC systems seems to have a little less power, and the antenna goes down a bit more slowly. Is this a "problem" or just a characteristic of the car? Or something with the battery and/or alternator?