Got the II 62 turbo all hooked up this afternoon and there is an unfamiliar rattling going on. I rechecked everything and made sure none of the studs or bolts were loose. Drove the truck and it doesn't seem to me like it has the power that it should with all of the recent upgrades even when i had the II 66. I pulled the codes up on the attitude monitor and I had a the P0251 code. I don't have a fuel rail pressure guage on it yet so not sure on the rail pressure. I've been reading about changing the FCA. Is the FCA and the overflow valve a good place to start?