yeh im guessing its cause your boost is set to 0.8 bar i believe you said and them 2 "boost cut restrictors" as you said were in the ecu might not be wired in properly i believe fuel cuts set to 0.75 bar, please someone correct me if im wrong id rip them out straight away them two horrible things lol id drive steadier and turn your boost down to 0.60 bar on your EBC till the ecu comes. when it does your free to set it to id reccomend no more than 1bar max lol