How much should I turn it down, I'm assuming I just turn that screw but how much? I've never had a problem with it and never changes the psi from what it was out of the box. If there is anything special please let me knowYou sure it isn't the raptor tripping the fprv because of too much pressure? I get that all the time when I turn the pressure up. Try turnin it down a hair and clear the code to see if it comes back. Shim kit fixed mine.