Ok, I finally got some time on my truck. Upon recommendation from a local expert, I tried unplugging the Fuel Pressure Regulator. I unplugged the FPR and then tried starting the truck. The truck would crank forever, but nothing. So I plugged the FPR back in and the truck started right up. After about a minute or two, the truck started idling rough again. I then tried unplugging the FPR while the truck was running and the engine stopped, just like I switched off the ignition switch. Tried it again just to be sure it wasn't a fluke with the same result. I then started the truck and when it started idling rough again, I unplugged the Injector Control Pressure (?) sensor while the truck was running rough and sure enough, the idle smoothed right out. I checked the plug and the sensor looking for oil, but I didn't find any. Would this mean that all I need is new ICP sensor, or is there something else this is telling me?

Thanks for your help, I'm looking to make it to the last couple of races this year.