Hey man

u got same problem as i do and someone else did

i put new post here with title: rough idling issue

ok u can narrow ur search by unplugging each injector 1 by 1
if u find that u unplug an injector and it gave u better engine working then others then its faulty one
in my case they were all same so its not ignition problem....

yeah im still woundering around as u do....