when I park in my garage, it smells like gas near my car... I'm thinking it's the gas cap. it doesn't smell like gas when I'm driving and there's no drips on the ground under the car. are gas cap seals known to go bad on 740s?

 

Replace the cap as they are cheap. Also look in the left side of the trunk under the liner and check to see if the rubber filler hose to the tank is cracked or leaking. You also might want to get under the car and check for hoses and look at the main fuel pump and filter.