Extremely low fuel pressure... im stumped..
 

I was driving from the gas station the other day about 5 miles from my house and the gauge was showing 18 psi fuel pressure. i look down 1 min later and its reading 2 psi!! im like holy shit.. i almost wreck trying to get off the road. i shut her down. get out the truck. nothing... so i drive her home on about 5-6 psi when i get home shes limping on 2 psi into the driveway. today i installed an inline filter, and changed the stock fuel filter.. my truck is idling at 17 psi stable... then i take it down the road and it drops down to 2 psi? im thinking lift pump? At startup when im sitting im my driveway doing nothing it idles at 17 psi but when i drive it and come back the fuel pressure wont rise above 5-6 psi.

Do you still have the stock lift pump or do you have an aftermarket set up?


Sent from my iPhone in the cab of a Caterpillar

What gauge is checking it? Manual, Electric, or like adrenaline or juice monitor? I would reference with a different gauge if you can. if not id say the Lift Pump is dieing. Is it a stocker or a aftermarket?

im almost positive its stock... the gauge is a 30 psi glow shift...

Try a manual gauge from napa for comparison. The glow shifts have a horrible track record of being unreliable. it may just be a sensor

i just called around and no auto parts stores around here have a fuel pressure gauge :scare2:

Can they order one in for you?

no they said they dont carry them... im trying to fix this cuz i work tommorow and i have no other vehicle to drive

hmmm

im thinking i should just get an fuel pressure tester and test the port on the injection pump to see if it has enough pressure

That would work as well

am i low on fuel or something? cuz when im on a hill thats when my fuel pressure drops..

Well when there is a load on the truck it will drop some. How much fuel is in the tank? if its low fill it up and see if it changes. You could have a 1/4 tank issue.

i have a 98 5.9 24 valve with replacement ddrp lift pump was running fine
now after about mile or two fuel pressure goes from 20lbs to zero
i have to pull over and shut truck off and let sit five min then pressure goes up good for another two miles so on

sometimes if driving i take my foot off pedal pressure goes back up

what can do this ecm ???

You have a restriction in your fuel system. Either your lift pump is not pulling the fuel from the tank or your fuel filter is clogged, or maybe you have some solid particulate in your tank that is being sucked in or around the fuel pick up. After letting it sit, it falls away and fuel pressure is restored. We had this on a big Peterbilt at work where someone dropped a rag into the tank. As common as the lift pump failures are on these, I would suspect that but I have seen fuel filters do this as well. Personally, I would replace the fuel filter first. I have seen many problems from aftermarket filters that get a little dirty and stop flowing. I personally also only recommend Fleet Guard or Mopar filters. Fleet Guard makes the filters for Mopar diesels. If you buy a Mopar, you are buying a Fleetguard.

Good Luck

okay so now i have installed a 100gph raptor frrp. the fuel pressure it 25psi when i bump the starter. i start the truck and after about a min. the fuel pressure drops and does not pick back up.

Have you checked or replaced the pressure regulator? It is built in to the return line Banjo bolt.