Start up gas smell

My 4.0L V6 is having rough time start up. Smelling gas. After a min and going running fine, just only at startup. If anyone can shed some light do at home mech work. thanks very much.

I believe got it solved replaced a conrol sensor for the fuel injection sits in front of engine block on left hand side. Unhooked battery cables for about a minute then let the engine idle for 10 min.