03 Sentra not starting

My 03 Sentra is not wanting to start. After pumping the gas and turning the key repeatedly it will finally start. The car tries to start and I can smell gas. We changed the spark plugs about 4 months ago. It is getting worse. Any suggestions? Thanks.:shakehead

And we got the code 303 from it.

That code is for misfire on cylinder 3, you may have a leaky fuel injector causing flooding, could be bad plug wire, also you want to pull that spark plug and see how it looks