2004 5.9 cutting out

[Jared 2004]

hi all need some help my 2004 5.9 cuts out at higher speeds around 65-75. my truck is stock but has had the lift pump relocated to the tank. I have no engine codes. any ideas??

 

[Killer223]

could be lots n lots of things. lest start with the basics,
Filters, fuel and air.
Then how about electrical, good batter connections, grounds all nice n clean.?

 

[Jared 2004]

Yes sir batteries are new all connections are clean air filter and fuel filter or new it has been doing this for over a year and is steadily getting worse also there are no trouble codes.

 

[cerberusiam]

Fuel pressure at the CP-3 inlet, rail pressure, and boost. Gauges are invaluable with problems like that, get some is my advice or you are just guessing and throwing parts at it.

 

[HHhuntitall]

If it's just falling off at throttle, like it's running out of fuel, the most common failure I see there is the lift pump failing. But as cereberusiam said, you'll need a guage of some sort to test it and confirm it. A simple lift pump fuel pressure test at the CP3 would confirm or eliminate the in tank pump as the culprit.

As a note, I often see the conversion kits where the lift pump has been moved to the fuel tank, even when installed from the dealer, develop corrosion at the battery and not get good contact to the relay that should be installed on the firewall between the driver and battery. Then there is a simple blown fuse in the main feed wire to that relay from the battery..... a simple test light in the driveway would eliminate this problem as a culprit, if you have any mechanical ambitions.

 

[Jared 2004]

Thanks for the info i appreciate it

 

[Jared 2004]

Thanks for the info

 

[WalterJ]

Thanks for the info i appreciate it

Update pls. Mine's in the shop for similar symptom. Mine stumbled oneday, then returning from small trip, it died 1/2mile from house & wouldn't restart...then towed...arrrgh. This 2nd in-tank pump only lasted 5 years; previous in-tank pump lasted 8.5 years...go figure.