what causes engine to barely start & run with gas pedal floored

sorry, I replaced carburator,and thank you for response

Oh, don't be sorry, a whole lot of people replace parts that they don't need trying to figure out the problem ... Since there are TWO CATALYTIC CONVERTERS > 1 front and 1 rear on these vehicles .. Did you happen to notice that small round *catalytic converter* that is bolted directly up to the 3 bolt exhaust manifold flange?? .. That will surely cause this problem if the internal catalyst fails and restricts exhaust flow!! .. Also flooding can be caused by gas entering from another source, like emissions piping..resulting in 'black' smoke from tail pipe .. Hope you get it fixed! http://www.ebay.com/sch/Mazda-B2200-Catalytic-Converters/33629/bn_1432597/i.html To see a picture of the 'front' cat, copy the link above then paste it on Google search... (BTW, it can be gutted)