Mystery - Strong Fuel Smell

After a 40 mile round trip at highway speeds last Saturday I parked the Lancer in the garage.

Water temp on the highway was 160 and only about 165-170 when I pulled into the garage.

Everything was normal.

20 minutes later there was a STRONG smell of gas throughout my two car garage.

I jacked up the car and scanned the bottom. No puddles, no obvious drips, gas cap was secure.

No leaks anywhere under the hood. No gas stains around or below the carb or intake.

If I leaned close to the air cleaner I could smell gas, but not really strong.

YOU GUYS HAVE ANY IDEAS?
lancer engine4.jpg