Dash showed P 0191 code, could this be from a clogged fuel filter? I just changed the filter and the truck seems to run better.

 

That code is for the Fuel Rail Pressure Sensor Performance. Don't know if the filter change will effect it or not. Good luck, Don

 

I've too have the P0191 code on my 2005 3500 CTD - now what?

Should I install a new fuel filter first, before taking to the shop for further daignosis. Engine runs great - no problems.

Thx, Rob

 

P0191 goes to rail pressure, rail pressure relief valve. They can momentarily stick open, loss of fuel pressure, throws code, then the valve closes and all is fine, no stalling when it happens unless you are sitting idling. Then things can run good for a while. I had the code 3 times in the first 2 months when my truck was new, finally the dealership replaced the valve, never had the code again.

CD

 

May just need a reflash, or retrofit transfer pump installed.
TSB 18-022-07 Flash: 5.9L turbo-Diesel Engine System Enhancements
Improvement to the Fuel Pressure Rationality Test to prevent possible false test
failures and the following related Diagnostic Trouble Code:
a. DTC P0191 - Fuel Rail Pressure Sensor Circuit Performance (2004.5 to 2005
vehicles)

 

Thanks for the replies!

Guess I'll contact a dealer service dept. and have it checked out.