I have a 2005 Hyundai Sonata GL 2.4, with 112,000 miles on it. Once in a while when starting the engine and windows down, I'm smelling gas. It doesn't happen all the time, and can't smell it inside the car with windows up. Also, once in a while it has a hard time staring. These things don't usually happen on the same day as each other, but today they did. But not at the same time. Spark plugs are new, no leaking fuel lines are seems, and recently a new EGR valve. No engine light or code. I think the idle is kind of crappy, but mechanic says it's not too bad. The smell is coming from the engine area, and the fumes dissipate quickly. What all could cause this? Thanks in advance.