boosted 95 coupe

ok so here is the deal.the car has a fully built 2.0 ls/vtec.it has a 3 bar map,and the ecu is tuned for all of this allready (the swap and ecu come out of a car and right into this one).what i am having problems with is the car is running so rich that it wont even stay running it just kind of spits and putters,if i unplug the 3bar it runs alot better but still not like it should (obviously) does anybody have any idea what could be my issue here?