[Rapid Ascent]

When pulling my 5th wheel (approx 12,000 lbs) up long steep (usually >6% grade at >2,200 RPM) I almost always get the P0251 code and sometimes get the P0148 along with it. When towing I keep my Edge J/A in #2 (Tow). Is something going out or is it just my Edge J/A putting something in over it's limit. :confused013:

PS
I looked up both codes and know that they are both fuel related.

 

[Rapid Ascent]

Bump!!!!!!

 

[steelhead01]

what type and how many miles/hours on fuel filter?

miles on truck?

any fuel system/ HPCR work done?

does it do it with the EJ disconnected?

any engine roughness or loss of power when towing heavy on grades?
get a scan gauge or scanner on it while driving pulling on the same pulls that produce the codes.
measure engine load and rail pressure. note any rapid variations at steady rpm and load.

may be fuel starvation, not a good thing in a HPCR, kills injectors

 

[Rapid Ascent]

Thanks for the response steelhead01. Here are the answers to your questions;

Current fuel filter has about 6,500 miles (I change at 7,500 with every oil change). It happens even when I have a new filter.

29,000 miles on the truck.

No fuel upgrades yet.

It does it with the Edge J/A on 0, but I have not tried unplugging it and running completely without.

No engine roughness, but it feels like backdown from the Edge J/A before it happens.