I have a question for you guys that know.
my fuel pressure at the fuel rail is 56 and engine running it goes up to 57psi.
When I shut the engine off and wait a hour or so I lose all the pressure at the rail.
Is is suppose to keep the pressure at the rail when the truck is not running?

I think I might have a leaking fuel injector, I have already replace the o-rings for the fuel injectors. I bought bwd Part # : 274081 Is this is a kit for 1 fuel injector. One for the rail and one for the bottom on the injector?
My gas mileage is at 11mpg. I have replaced map sensor, throttle position sensor, Intake air temp, oxygen sensor (front ones) crank and cam sensor.
I ran fuel system cleaner too with no luck. I did this all before I found out that my fuel rail
loses pressure when it sits overnight.

How can I tell if I have a leaking fuel injector?
Could this be a leaking intake valve?

any help will be greatly appreciated as I don't know if I need to replace the fuel pump or the fuel injectors?

2004 Dodge Dakota
4.7L engine
4x4

 

I don't know anything about the injectors, but it could be your fuel pump bleeding off.

 

when you prime the pump with engine off whats the psi. and yes there are 2 orings one on the rail and on the injector head. are you leaking gas from the fuel rail?

 

when I prime the pump with engine off its 56psi
also fuel mileage is 11mpg. I had injectors leaking at the fuel rail on the drivers side rail.
I only replaced those o-rings top and bottom. I can see where the fuel is spraying on the plastic plenum. I am just trying to find out why my truck gets such bad fuel mileage.
starts and runs fine though. 454rfe transmission uses a little fluid though but was told that it was just seeping out. when I changed the fluid at 40,000 miles I used rubber gasket instead of the black rtv. Fluid looks ok and when I changed fluid I used both transmission filters, the spin on and the regular filter.

 

if you can see gas spraying on the intake manifold then you either have more orings that are toast or you didnt put the injector in correctly. are they pressed into the rail and head all the way? from what you are saying it seems your fp is fine. i would fix that gas leak quick. same thing happened to me a few months ago. one orings was destroyed and i had stupid amounts of gas going everywhere in the engine bay.

 

I only did the drivers side fuel injector o-rings and when I did them I only pulled up the fuel rail on the drivers side. I only pulled up the fuel rail on that side and put in the top and bottom o-rings. With the kit I bought I don't know if the o-rings were the same size for the top and bottom. but looked like the top ones were thicker that went into the rail.
when I put them in I oiled the o-rings with oil and pushed them into the fuel rail far enough to slide the locking clips in. I checked twice to see if the clips slid in to the injector. When I put the injectors in to the cylinder head they went in all the way and where the two bolts that hold the fuel rail on they were flat against the block.
I don't see gas on the other side but will replace them as soon as I can.
I think I am going to purchase rebuilt fuel injectors from ebay. lifetime warranty 4 hole injectors for $130.00 not a bad deal I think??
I might have a stuck open fuel injector that is leaking when the engine is off causing the bad gas mileage. It only happened one time but after work my truck was hard to start. I had to crank and crank the engine before it started but after that I replaced cam and crank sensor and it did not happen again. I am unsure but the injectors could be leaking internally flooding the engine and that is why it is hard to start, that is what a mechanic told me but he could be wrong. I don't trust any mechanics around here and that is why I do all the work on my truck. He also told me that my exhaust manifolds might be leaking causing more air to enter and that causes my oxygen sensors to put in more fuel.