I had an experience lastnight while plowing snow. I was dropping fuel pressure even while idling the truck. I usually get about 21psi at idle and 15 at WOT. Now I was getting 16 at idle and 9psi at WOT.. thought sure this is a perfect time to loose a lift pump, on a jobsite at mid night..

I searched for leaks, checked the fuel filter. Everything looked fine.
Come to find out the locknut on the pressure regulator came loose. With a few adjustments and a few turns on the locknut I was back in business. Held 22psi at idle and 15psi at WOT while pushing snow..
I just thought is share this with other Raptor owners, maybe check the locknut every oil change to help prevent a headache while the truck is not in the driveway...

 

Thanks for the heads up im about to install mine this week

 

I didn't even think to check mine when I installed it, Bet I do Now! Thanks!