Im thinking along the same lines. As its only under very specific conditions, ie throttle possition and engine speed. As I said under boost it pulls fine which to me rules out a spark issue as surely when the cars being driven hard any weakness in the ignition side would show up more? I dunno. Thankfully I have a mate who also has an S12 and im gonna pop over to his later to borrow his afm off his car and see if that makes a difference. Also trying to source an afm just incase. Will keep you posted.
