My 93 chevy blazer will not start?

i have a 93 chevy s10 blazer 2wd 2d. i started it the other day and tried going into reverse and i gave it gas and it bogged out really hard. so i pushed it to floor and still bogged out hard. and now it wont start. it had trouble starting before. u would have to push on pedal while trying to start and it has the 4.3 vortec cpi. i changed fuel filter on it, distributor cap and rotor on it, has new wires and plugs. the fuel pump is working, and when it cranks over it tries to start but wont go through with it. and after you try starting it you can smell fuel inside engine compartment. any ideas?