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garrettg.bpd
February 13th, 2016, 04:45 AM
Im fighting lower fuel pressure on a 07.5 6.7. The rail pressure drops off after 2000 rpm on a stock tune. The turcks history is unknown for sure. The used car lot said that it had "upgraded injectors" and that the fuel filter had been changed. On my inspection i found that the fca is new and a rail plug was installed. Retorquing the rail plug help a little. So it was replace with a new releaf valve that i shimed with no change in top end fuel pressure. Any insight would be great thanks. 19250

2007 5.9
February 13th, 2016, 03:09 PM
I vote dead pump

garrettg.bpd
February 13th, 2016, 03:18 PM
Cp3 or lift

garrettg.bpd
February 13th, 2016, 03:23 PM
Stock lift pump. If unpulg the fca fuel pressure will max at 29k. Tuning the fca has little to no change.

2007 5.9
February 13th, 2016, 05:34 PM
Id say cp3..pulling the fca at idle won't tell you much other than you don't have a HPR leak...the fact that fca goes 19mA with a 16-1700uS pulse...in my experience is a very weak cp3

kenturbo
February 16th, 2016, 04:21 AM
had a rash of these the past year, screen at base of fuel pump plugged, cleaned screen and good to go

ace22487
August 6th, 2017, 08:03 AM
Hey guys, Just figured I could update this post.

This is my truck Garrett was working on. The CP3 failed around 10/16. We pulled the truck apart and did a pretty major overhaul. Turns out the Injectors were R1 units from I.I. The cp3 was a factory pump and just couldn't keep up. We put an 85% over cp3 and R2 Injectors on, along with milling the intake manifold off, and replacing with a b&b tooling one. Truck runs great now.. The factory turbo won't push much over 30 psi because the restriction removed from the system.. also the trans. isn't too happy with all the new power... ITS ALWAYS SOMETHING!!!! :grd: