Fuel pressure
 

I recently put a triple pillar gauge pod in my 2001 24 valve. My fuel pressure is at about 13-14 psi at idle and will drop to 8 at full throttle. Is this normal? Is it low? Lift pump is about 9 months old and fuel filter is changed at every oil change. Kinda new to the cummins but wanna upgrade to a better lift pump (fass or equivelant) thanks for any help

Your seeing normal pressure for the stock lift pump. I would hotdog it to much tho lol. You can get much better performance from a FASS or Airdog system I generally see about 15 PSI going down the road with the Airdog 150. Some folks are saying airdog's quality slipped so you may want to look at FASS. :tu:

FUEL SYSTEM PRESSURE

Fuel Transfer (Lift) Pump Pressure With Engine Running Minimum 69 kPa (10 psi)

Fuel Transfer (Lift) Pump Pressure With Engine Cranking Minimum 48 kPa (7 psi)

Fuel Injector "Pop Off" Pressure 31,026 kPa (310 bars) or (4500 psi ± 250 psi)

Fuel Injector Leak-Down Pressure Approximately 20 bars (291 psi) lower than pop pressure

Fuel Pressure Drop Across Fuel Filter Test Ports 34 kPa max. (5 psi. max.) at 2500 rpm (rated rpm)

Overflow Valve Release Pressure 97 kPa max. (14 psi.) at 2500 rpm (rated rpm)

Thank you for the info. Ive been looking into getting a fass pump anyway, more reliability!

Glad I found this thread before I started new one. I am seeing 11-12.5 psi at idle, and have seen it dip as low as 7 when I jump on the truck. Judging by what has been said here, it is probably best to not jump on the truck too much until I get a new lift pump on the truck.lol

I would like to add a question here though. We removed the catalytic converter and everything behind it, so the truck is basically running a modified stock straight pipe at the moment. The fact that it sounds bitchin is besides the point here.lol I did notice a slight drop in fuel psi at idle but the psi seems higher while driving now. Is that normal?

I would say that the modified exhaust is totally unrelated and by the way the first year for any kind of catalyst was around 2004 I think then it morphed into the SCR DPF in 2007 and after. The small catalyst chamber that the older trucks have I believe is just a resonator.
I forget what kind of lift pump are you running?

Good to know. I was assuming it was part of the CA emissions crap the truck had. It runs better and I can hear the turbo whistling now. I've got a stock replacement lift pump on it now. Napa special.

Sounds like it's working good for a stock lift pump. In my opinion the vp 44 got a bad reputation from the stock lift pumps failing completely and starving the pump until cavitation seizes or wears the pump out. All of this going on while the driving fat , dumb and happy because he has no indication of fuel pressure in the cab.
The Vp pump in my truck has over 200,000 miles that I have put on it. Not sure if it was changed durring the first 100,000 of the trucks life. I would say IMO that if you have good positive pressure showing on the gauge your pump will live a long tiime.

It never hurts to upgrade the pump a little though, right? I am setting the truck up to become the family ride for awhile, so I need to make sure it as rock solid as possible. I will move this discussion over to my other thread so as not to steal this one. Thanks for the info. Hope my question has helped the OP as well!