I have a slight prob with my auto ef.
When you accelerate from a standing start it stutters for a split second then it gets going, also when you jam the brakes on hard it almost stalls.
I have a new isc and have adjusted the tps to .80 volts previously and just rechecked this.
Mods are as follows, extractors, 2.5 cat,and redback zorst, modified elintake pipe, xr6 turbo snorkel, 3inch cai under the airbox, vernier cam gear 4 deg advanced, 3.45 xr diff, pod in the box.
I reckon it feels like an isc or tps prob but im not too familiar with the 4.0.
I thought the advanced cam timing would help it off the mark, and it does but it certainly didnt fix the problem(it used to be worse.)
It idles at about roughly 650 rpm in gear.Fuel filter has been replaced.
Could it be dirty,clogged injectors? Gets 500km to a tank city driving.

Maybe check the resistance in your ignition leads if they are high or not within specifications replace them.Also check your fuel pump pressure and flow.At idle it should be around 240kpa to 300kpa depends what sort of reg you run.A pinch pressure of more than 600kpa (this is where you crimp the flow line on the other side of the gauge for a split second and observe the fuel pump spike in pressure.Also the flow rate should be more than 2L per minute.If once you have checked these things and have come to a conclusion tha tthey are fine.I wip the injectors out and get them cleaned.