My 01 mustang 3.8 starts to mist and sputter after normal driving every 35 to 40

It has a new coil pack,new cam and crank sensor. But most importantly is the fact that when it starts to sputter after about 35miles of driving.I put the car in neutral and turn the key off and start it back it stops sputtering and drive normal for 30 to 40 more miles

sounds like an elect break down. ford has whats called the wiggle test believe it or not. try wiggling wires to coil pak and inj to see if that will duplicate the issue. just asking where did you purchase coil pak? iv seen after market ones break down even though they were new

Autozone but my thing is why does it stop this problem once I re-entergize the power with the key switch. This is a 3.8 we talking about

hard to say but when you shut off ignition you automatically reset computor. you may have a corrsion issue or a loose connection which can cause high resistance in wiring