Engine starting problem
 

It all started about 2 months ago, i had put my 240sx s13, ka24e, it started feeling like one of my spark plugs wasnt firing right but i replaced all of the wires and plugs and it helped some but it was still messing up. then it stared to not start, it would crank up and then die unless i gave it some gas quickly, when it would die it would usually crank up after about a minute or two of cranking and pumping the gas. now it wont start up again after it dies the first time. i know that it is getting gas because i can smell it. another is whenever i go to shift or just give it gas, i push the pedal my rpms drop out like i am flooding the engine, when accelerating while in gear it jumps really bad. my friend who is a tech. said check the mass air flow sensor but i dont think that would keep it from starting. i would really appercaite any help anyone could giv on this matter it is a pain in the butt.
David Morgan