Yes. If control is all hooked up and isn't connected good it will max out rail pressure. Not sure how it works exactly but it splits the system and when it doesn't have good connection it will do that. Luckily I had just read about it and was logging my truck at the time and found the loose...
Sounds like you need to figure out what you actually have in the truck first. If sensors are swapped, wrong reluctor wheel or loose connections will cause this.
We went built motor with it, but it had a stock cp3 in it before built motor. It fires up now every time and rail holds at 6k psi at idle. Revs up in neutral to 4K but brake boosting it only goes to 1500rpm then stops.
Did it give you any codes or would it not just build rail pressure? This on started and ran with no codes and held rail pressure but now it won't get over 120psi while cranking.