When it gets cold outside and it's been humid the night before, my 1996 Olds Ciera doesn't start in the morning. It's happening more and more often. It turns over just fine, but the car won't start. In the front, the fuel pump relay clicks - I've already replaced that - and there's a hum from the back (guessing it's the fuel pump - the fuel line feels like it's pulsing when this happens). I leave the key in the "on" position and the humming from the back gets louder. Once the humming stops, the fuel pump relay stops clicking and the car starts every time right away. Once it's started, it runs fine - no stalling or power loss. When it's warm, this never happens. I just changed the plugs and wires and the fuel pump relay. Before I drop the tank and go after the fuel pump, any other suggestions?