are you sure you have the right firing order, perhaps you mixed it up when doing the wires!

I also am having a similar problem!from standing start or on hard turns when tank is below half the car goes then coughs and then catches up to itself!!I have been told the baffle in the gas tank that keeps fuel pump encased in fuel mat have broke off!this would cause a starvation when fuel sloshes away from pump!I have not checked mine,to cold in garage, but I think you may have same problem!! My problem started all of a sudden, car didn't get worse gradually,one day great next day bad!!if lots of fuel doesn't do it!!

Good luck!!

try the fuel filter first,, about the easiest to do if it has not been done in a while