Stuttering and dieing at 2-3k

[s13eater]

my afm packed up so i tried another 2 which did not work, 1 of them would not tickover, then went like a bastid on boost, the other ticked over perfect then run crap between 2 and 3k, then i had a cracked wire near the plug that made it tickover crap, then i had a cracked wire on my fj20 lead to the afm, that ran crap allover,i just don't know what to sugguest, oh yeah, check your afm