Check your fuel pressure regulator, pull the vacuum line off and smell for fuel when they fail you'll get gas fumes in the engine compartment. Here's a online guide to change the regulator http://bit.ly/6hCS5 and the parts run about $68 to $132 at the dealer or at autozone $55 http://www.autozone.com/N,14900165//shopping/partTypeResultSet.htm Hope this helps.
check the fuel tank area, The fuel pump is located in the fuel tank so there's a fuel pump seal that could be leaking and the lines coming from that area heading to the front of the vehicle also the filler neck could be leaking. better have a technician put your vehicle on a lift and locate the fuel leak.
It can be very hard to find a small fuel leak. Check around the car and see if you can pinpoint where it is coming from. Is the check engine light on? A fuel vapor leak from the EVAP system should turn the light on.