March 30, 2022, 09:22 PM
Bruce WilliamsDuramax low fuel rail pressure?
I use a 2006 Duramax LBZ dually for towing our race car trailer.
On long grades under heavy load I get the low fuel rail pressure code.
Truck only has 65K on it. It gets regular oil and fuel filter maintenance.
I have replaced the O rings on the fuel filter head.
Truck sits most of the time. Just gets used on race day.
I run an Edge Attitude with juce programer which allows me to pull and clear the code on the fly which is nice. Im getting ready for the upcoming las Vegas race in April and would like to see if I can get the codes to stop.
Any ideas if a lift pump can cure this problem?
March 30, 2022, 10:06 PM
banjoI had the same problem on my truck. There is a pressure relief valve that gets weak. They sell shim kits to increase, or you can go with something like this. This fixed the problem on my truck.
https://ppepower.com/collectio...riant=42081658077427March 30, 2022, 10:09 PM
rustyt is not a weak CP3 pump,i have had this happen to my LBZ sevaral times and heres the most notorious ones..
weak FRV(Fuel Rail Valve),how to fix is either replacing with stock,putting a shim kit in or a race valve in.
Injector Control Mobule Harness,if it is bad it will cause stuff like that also.
bruce this was from a forum
March 30, 2022, 10:13 PM
banjoHere is also a link that explains what is happening and how to test.
https://kennedydiesel.com/docs...tle%20Test%20etc.pdfApril 03, 2022, 02:56 PM
AlaskaracerEarlier years have an issue with injectors as well. Excessive bypass. I'd have it taken to a reputable shop for diag.....I've done A LOT of injectors on those.......