i have a 2005 w5500 gmc medium duty truck. I Was Driving and it bucked. It did it again about 4 different times threw out the day.(lots of starting stopping, used as a tool truck). At the end of the day i lost all throttle power. I was driving along and rpm's dropped to idle and the gas pedele would do nothing. I could step on it but it would not change the rpm's. turned off the truck and everything worked fine. now it is happening all the time. I have a p1094 code. anyone have ant ideas? thank you. Quentin
P.S.-first time using this site, looks good:)

Moved to Medium Duty Trucks


:welcome2: to the forum

Code: P1094
Modules: PCM
Description: Fuel Rail Pressure Low During Idle or Decel Fuel Cut-Off (DFCO)

First thing to check is the Fuel Pressure Regulator (FPR) next would be the fuel pump itself.

will check that. thank you. is the description fuel pressure low (p1094) the isuzu description. Sometimes with these w5500's the code has a different description (or so i'm told)

That description is for the Duramax. You can look up DTC codes at this link (part of this board): DTC Code Lookup (http://www.dieselplace.com/forum/dtc.php)

Lots of information available here if you use the search function on P1094.

Just got the truck back from having 1 injector put into it. The isuzu dealership said that this was my problem. The truck is still running bad but only after it gets warm. If i try to start it it will not start. I have to manually prime it to get it to start. You mentioned to check the fuel pressure regulator. Is there a way to check that it is working correctly or do you have any ideas. Thank you. Quentin:confused:

When was the last time the fuel filter was changed??

There is a very small screen in the lift pump. If you remove the bolt on the line from the fuel filter to the lift pump... on the lift pump side. Look in the end of the bolt. There will be a small screen that unscrews from inside the bolt. It is a pre-screen to your lift pump. That was the problem on my Npr. Hope this helps.