raw fuel smell

[Volvopassion]

I own a 2012 S60 that has only 3500 miles. Since the car was new I noticed that after driving it for about 20 miles or more and then park it in the garage within 10 minutes or so I smell raw gas coming out of the engine compartment. The smell goes away as the car sits and engine gets cooler and then goes completely away. Smell is more noticeable when the car is in an enclosed area such as a garage. I have located the smell coming out of the area where the fuel injectors are. However, I notice no wetness in the area and no leaks on the garage floor. The dealer tested the area with a meter and nothing is registered so, they said there is nothing they can do. The dealer's mechanic, I went to, did not even offer any ideas or possible causes. I suspect there must be something under the area of the engine I smell the fumes that is the source of the problem. Is there any fuel lines of associated fuel components under there that either myself or a competent mechanic can check for?