Car won't start sometimes.

[jon987]

Every now and then my 240 won't start or it'll start and die right away. I bought a new distributor cap and rotor cause they were worn and also spark plugs but it's still happening, it just cranks like it's trying to start but it doesn't. When I try to start it, it smells like gas under the hood and I press the gas pedal a little on and off and it'll finally start. Anyone know what could be wrong? Thanks for the help.