Fuel leak

[bulldogfan5]

Hello all,
My wife's 08 pt cruiser (2.4l non turbo) filled the garage with gas fumes over night last night. She drove the car 8 miles to work this morning and her miles to e estimate went from 95 to 76. When she left work she put a little gas in her car to make sure she made it home. It was at 154 when she got gas and 6 miles later was at 142. I checked every fuel line I can see with the exception of on top of the gas tank and found no visible fuel leaks. I drove the car on a 5 miles loop around the block and the mpg estimate said 22. During this 5 miles the miles to empty calculation went from 142 to 130. When I turned the ignition off I could hear a slight hissing noise coming from the front passenger side of the engine. Is there anything on that corner that could be leaking fuel? I have taken the intake manifold off so I could inspect the injectors and it does not appear they are leaking unless it is evaporating and not spraying....btw the check engine light is not on. Any help would be very appreciated!
Thank you!

Edit: I can only smell fuel when I am laying on my back underneath the front of the engine.