[EMC2]

i have a tuned ecu for 740cc z32 maf gt2871 .64, and cams, anyway my trouble is it pops and sputters when im at low throttle then when wot it pops then revs but revs slow then will back fire and half the time die. timing is set dead on 15 deg also checked for vacuum leaks and boost leaks, ecu throws no codes except 55, the wire off the back of the coil harness when touched to engine or ground will make car run even worse, also the ground was hooked up before tune and car ran well, where does that wire go? any ideas or help would be great. thanks