normal driving it is fine. plugs,wires ,fuel filter and flow are fine.cleaned intake,injecters and vavles. no codes under globalobd2 or manufature specic. looking for suggestions possibily missing something.
we have a 2006 ford freestar at shop that under heavy acceration it will surge on 2006 Ford Freestar
maybe a vacuum leak
Have you driven / ridden in it with fuel gauge and scanner hooked up?