85 carb question

[bbchevy]

i,ve got a 4.3L V6 in my 85 pickup. 4bbl Q-Jet, factory headers, etc. all stock. for some reason, the motor wont stay running anymore. it seems like its too lean. hell, maybe its too rich. once i get it started, i need to give it constant gas to keep it on. and when i go down the road, it has NO power at all. i have to drive with two feet... its not cool at all.i replaced the plugs, wires, cap and rotor. have a fuel filter, thats next. but how do i start to fix the problem. also, the secondaries seem to flood. they did that even before this started. please help me