starting problems

I have a 1997 Monte Carlo with a 3.1 litre engine. When the car is parked in direct sunlight with the hood down sometimes the engine will turn over but not start. I can raise the hood from anywhere from 3 min. to 1 hour and then it will start. The color is a dark maroon and I was wondering if the sunlight could be heating a component to prevent starting. If parked in the shade or at night or if outside temp. is low there's no problem. The car has never died after being started and runs great.