2002 LB7 powerloss new guy here

ryanford

New member
Jul 20, 2023
4
0
1
wyoming
cp3 is fine replaced injectors fuel air filters airflow sensors truck runs will not go over 2200 rpm falls on its face i can get about 60mph out of it if i take my foot offf and let it shift? $7K in and none of the dumbasses around here can fix it i have a fass lift pump in a box but i dont think is going to get it. cp3 when tested is making 135 145 while power braking as soon as the truck is moving it falls off ? NO CODES AT ALL!

P.S, GOODRUNNING STRONGTRUCK I LIKE IT VERY MUCH.
 

2004LB7

Well-known member
Dec 15, 2010
6,394
1,755
113
Norcal
Welcome

Also, double check you are not getting air in the fuel to the CP3 with a clear hose. If all is good do a return rate check on the injectors, cp3 and pressure relief
 

ryanford

New member
Jul 20, 2023
4
0
1
wyoming
Welcome

Also, double check you are not getting air in the fuel to the CP3 with a clear hose. If all is good do a return rate check on the injectors, cp3 and pressure relief
yes starting to think fuel pressure valve
not sure had 2 master mech. put high dollar snap on puters to it no codes again mystery
 

TheBac

Why do I keep doing this?
Staff member
Apr 19, 2008
15,324
1,610
113
Mid Michigan
Moved to LB7 section.

Where did you buy the injectors from? Not "top notch".
If you have a log of the CP3 pressures when the issue is happening, post it.
 

Chevy1925

don't know sh!t about IFS
Staff member
Oct 21, 2009
21,176
4,958
113
Phoenix Az
Removing my help after reading your comments. I see why the master techs were no help to you.
 
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