What exactly needs to be done to the calibration on an 05 f150 when you go return style? I maxed out the voltage fuel pump table to 15V. BUT the fuel pressure regulator sensor is still hooked up, I of course disconnect it because the truck is return style now, but once I disconnect that regulator sensor, it shuts off after 5 seconds or so and the fuse 34 pops which is the injector pcm fuse, after that fuse pops, the truck doesn't crank nor the hptuners can connect to the pcm. Once I put another 20 amp fuse everything is back to normal. You can see the fuel pressure fluctuating on the mechanical regulator gauge when the fuel pressure regulator sensor is hooked up as I'm assuming the pcm is modulating the pressure.