Gas Smell

My 2000 v6 Toyota Camry has a very strong gas smell that makes my eyes water on start up. It only happens once in a while(can go for weeks with no smell) but it is actually scarey when it happens and people near the car sometimes comment on the smell too. I have had my mechanic look at it but it hasn’t happened while it was at the shop. Any thoughts on what could be wrong?

Have the O-rings that seal the fuel injectors to the fuel rails and to the intake manifold inspected. These O-rings can leak depending on how the vehicle is driven and on how hot the engine is.

The mechanic will look for witness stains on the intake manifold where gas may be leaking from the injector O-rings.

Tester

Is this after a fill up?? Does the fuel level effect the smell at all??