What should the fuel pressure be for a 2006 6.0? If I can believe my Chinese pressure gage I have 50psi when the pump is running and 40psi once the pump is off. It holds at 40psi. The engine is hard starting and will run for a second or 2 and as long as 20 seconds and then stops. I have no idea how old the fuel pump is. 255k miles on this one.
Fuel pump pressure
- Thread starter Jimmyy
- Start date
Disclaimer: Links on this page pointing to Amazon, eBay and other sites may include affiliate code. If you click them and make a purchase, we may earn a small commission.
rockola1971
Full Access Member
What is the pressure at idle? How about 2k Rpm's?
noodlesandsam2
Full Access Member
Fuel Pressure, and does the pump run are two different things. I would get about 100K per pump in the 01 1500. Pressure means you start easily, but if the pump is getting old, and decides to stop pumping, you can stall. I would do the pump for sure at 255K - it may solve other crimes as well. It's not a fun job to do the correct way. When my 01 got to 250K, and the pump died, I went the route of cutting the floor above the tank, and pulling it. I did do the tank drop in the past, but at the end I was too fed up. The 'new' 02 2500 has both pumps new, and I did not have to do it : )
Jimmyy
Full Access Member
Doesn't run long enough to check. Mostly it run for about a second. It's not the pass lock because it did run for 20 seconds but I didn't have the gauge on it.
Last edited:
Jimmyy
Full Access Member
I picked up a new AC Delco fuel pump from Rockauto.com. I'll be farming this job out. I'm guessing there's about 8-10 gallons of fuel in there. I replaced one in my Safari van years ago and that wasn't very fun. From what I can find on the Google machine it should be 60+ psi with the pump on and 50 psi sitting.
Might be good to consult service data before throwing parts at it. Haynes (not the best, but...):
For fuel pressure, according to Haynes:
KOEO (key on, engine off)
Flex Fuel: 48-54 psi
Non-Flex: 55-62 psi
Easy enough to test without running the engine.
If the pressure is in spec, turn the key off and see if it holds somewhat steady or drops like a rock.
For fuel pressure, according to Haynes:
KOEO (key on, engine off)
Flex Fuel: 48-54 psi
Non-Flex: 55-62 psi
Easy enough to test without running the engine.
If the pressure is in spec, turn the key off and see if it holds somewhat steady or drops like a rock.
Jimmyy
Full Access Member
So today I tried the truck, it started hard but kept running this time. So I decided to check my work. This time with the key on 45psi instead of 40psi and 55 psi at Idle. Still going the replaced the pump, for peace of mind. Thank Fless, I can confirm those are good numbers.
rockola1971
Full Access Member
55 PSI at idle sounds good. Whats the exhaust smell like? Fuel? Maybe you got leaky injector(s)?
Jimmyy
Full Access Member
I was having a no start condition. It held the 40 and 45psi for ten minutes with no decline in pressure. I don't drive this truck much so it could be gunk in the tank messing with the pump. We have 10% ethanol here and i know when the gas sits you can end up with a waxy build up in the tank. I need to drive it more or spend more on ethanol free fuel, or run Seafoam in a few tanks a year.
Where's the research that shows ethanol causes gunk? I've been running "E85" (69% ethanol) 97% of the time (100% when it's available) for at least three years, my SUV can sit for a couple of weeks without being run, and it's never experienced any gunk issues.
On yours, when you say it held the 40 and 45 psi for ten minutes, is that after the engine was turned off, or still idling/running?
Your prior comments about 50 psi with it running -- that seems a bit high for these, although I'm not too familiar with the 6.0L. Do you have a fuel pressure regulator on the fuel rail?
On yours, when you say it held the 40 and 45 psi for ten minutes, is that after the engine was turned off, or still idling/running?
Your prior comments about 50 psi with it running -- that seems a bit high for these, although I'm not too familiar with the 6.0L. Do you have a fuel pressure regulator on the fuel rail?
Jimmyy
Full Access Member
When ethanol sits it turns bad. I replaced a fuel pump in my B3000 and there was some goo in the bottom of the tank. Kind of a waxy looking gunk. In small engines it clogs the jets in the carburetor. This takes 4-6 months. With a fresh supply running through its a excellent cleaner. When I had 40psi the truck would start and run for about a second and die. Yesterday it started hard but kept running like normal. So I decided to check the fuel pressure. I had 45psi with the key on, and 55psi at Idle. The needle was bouncing so yeah it could have been 50psi. My $13 Chinese fuel gauge could be off some. The extra 5psi made the difference. Not sure on the fuel pressure regulator all I could find online was the 2004 does have one. Rockauto doesn't list it as a part for 2006.
Any gas will gum up and clog a carburetor jet if it sits that long; that's bordering on abuse IMO. I always run only ethanol-free in my small engines and add STA-BIL to any fresh gas I buy. And run the gas out at the end of the season. I can't tell you how many mowers I've picked up in springtime because people didn't run the gas out in the fall. Get 'em for free, clean the carb and service 'em, and sell 'em or give 'em away.
So the E85 in mine must get cycled through fast enough to not experience the gum-up.
So the E85 in mine must get cycled through fast enough to not experience the gum-up.
Jimmyy
Full Access Member
Back in 2000 I was doing some work out in Buffalo NY, at that time I was working with a gas station chain. They had just started using ethanol in there fuel. They started having lots of problems with the ethanol going in to the storage tanks at the station stores. It had loosen up a bunch of crud in the tanks and ended up in customers cars and killed their fuel system. The "fix" was to pump the fuel out of the storage tanks and add it back in to the bulk tanks (millions of gallons in the bulk tanks), and to replace the type of filters on the stations pump. This wasn't the waxy gunk from sitting but the cleaning action from the ethanol. Ethanol is a thing in my opinion because Iowa is/was the 1st primary state. A ethanol plant can not run itself on ethanol. They are trading Natural gas to turn it into alcohol.
rockola1971
Full Access Member
Ethanol is corrosive and it will attack aluminum carbs. Ethanol also attracts water which will cause all water droplets in your tank to collect in one area with the ethanol and then when it gets sucked up by the fuel pump it will cause your engine to not just run rough but not at all because the engine wont run on pure water once that pocket of water is in your fuel rail. Any gas will start breaking down around the 6 month mark and cause havoc on just about any fuel system from carbs to fuel injection. As @Fless said, never leave fuel in any tank over winter if the engine isnt going to be used in that season enough to cycle out older fuel. So if you have to store a vehicle over a long period be sure to add enough stabil into it to keep the fuel from breaking down.
Jimmyy
Full Access Member
$600 for labor to replace the fuel pump. Good deal or bad deal I don't know. The test will be to let it sit for a few days and see if it fires up like it use to. In the past couple of months if it sat over 3 days and it was getting hard to start.
kurtibm
Full Access Member
The Mitchell book time for the job is 3.2 hours. I guess their shop rate is 185 per hour. Ouch!
Last edited:
In my 2003, inserting the key triggers the computer to start the fuel pump anticipating a start. Not sure when the computer figures after what length of time to forget that. Fuel pressure will slowly dissipate, and if you are monitoring that, I think removing the key is needed for the true reaction. My service tech told me 80 psi is about normal.
Possibly your car is a "Flex" fuel version. A sensor in the fuel line detects what fuel by optically detecting the type and tells the computer to change injection and timing. Google this: "can e85 damage my engine"
Yes, it's the L59 with an OE physical alcohol sensor.
When I google those words, most of the results are about using E85 in a non-FF system. Obviously that's not going to be a good situation, as the system isn't engineered to use that high of a percentage of alcohol. The corrosion "issue" is described in the link below, with possible damage when storing the vehicle. The solution presented is to have a full tank when storing.
Clearing Up Myths About E85 And Ethanol: 16 Things You Need To Know
Technical expert Jeff Smith sorts out the details of using E85 and deciphers some of the myths. If you want to get on the corn, this article is for you!
Unless I'm traveling, my tank level seldom gets much below 1/2, but normally it does sit for a week or two at a time. Nothing long-term.
