Fuel pump issue???

[410Fortune]

it could be the fuel rail or injector was just not seated properly or the o ring is torn, Did you lube the o rings when you seated the injectors?

 

[Turdle]

it could be the fuel rail or injector was just not seated properly or the o ring is torn, Did you lube the o rings when you seated the injectors?

Yes--is that bad?

I see no sign of a fuel leak. I have long suspected the immediate drop off of fuel pressure was a bad sign--I even replaced the o-rings when I installed my headers.

 

[rocket 5979]

I have brand new (in 2003) from Ford Racing (Summit) 42lb flow matched injectors.
The green ones with "new style"spray bungs--they have around 10k miles on them, but I am sure they behaved this way from the beginning- -pressure drop off. I always thought my oil smelled a bit gassy when I changed it, but cammed engines sometimes do this--

no cylinder misfire codes---

IIRC you have a newer FPR and you also have new injectors as well as a new fuel pump. I am betting that your fuel pump is bleeding fuel pressure backwards through the system and that is why it is not holding pressure for any amount of time. Either that or maybe a spring is bad in your FPR. Also, did you set fuel pressure at idle or with the truck off??? You have an A-1000 FPR with boost/vac ref port don't you?

 

[rocket 5979]

Yes--is that bad?

I see no sign of a fuel leak. I have long suspected the immediate drop off of fuel pressure was a bad sign--I even replaced the o-rings when I installed my headers.

If you had a bad o-ring then you would know about it almost right away due to your pressure dropping as fast as it is. You would see and especially smell the gas coming from between the injector hats and the injector body. I doubt it is this unless you just aren't that observant. :

 

[Turdle]

Also, did you set fuel pressure at idle or with the truck off??? You have an A-1000 FPR with boost/vac ref port don't you?

Yes--
The pressure is set to 43psi static--
When I re-connect the vacuum line--it idles at 40 psi.
funny--
fuel pressure holds (key on engine off)--i hear no fuel pump running, after the initial priming run stops, but as soon as the key is switched off, fuel pressure drops---

could there be a no power condition, in the pcm, switching an injector on? Maybe a short circuit developing when power is off?

 

[Turdle]

I doubt it is this unless you just aren't that observant. :

hey--don't be so hasty---

Anyhoo--is there a flourescent type dye I can use for this??

 

[Turdle]

hey--don't be so hasty---

Anyhoo--is there a flourescent type dye I can use for this??

SEARCH!!!!!!

 

[jah81592]

If you have a way to "crimp" of the return line if the pressure stays up then you will know you have a bad regulator then replace bad component. If you crimp the return line and immediately loose pressure then you have a bad injector. Now which one? That'll be up to you......
btw-If I shut my truck off the pressure will hold for around 5mins till it s l o w l y starts to bleed off. This process will not happen in a minute or anything like that,though.

 

[rocket 5979]

SEARCH!!!!!!

I would not bother with that dye. Just use your shop light and 10 minutes of real thorough lookover in your engine bay at your rails.

 

[rocket 5979]

If you have a way to "crimp" of the return line if the pressure stays up then you will know you have a bad regulator then replace bad component. If you crimp the return line and immediately loose pressure then you have a bad injector. Now which one? That'll be up to you......
btw-If I shut my truck off the pressure will hold for around 5mins till it s l o w l y starts to bleed off. This process will not happen in a minute or anything like that,though.

One thing to mention... If your running a steel braided return line then I suggest against crimping it.

If it is steel braided then just detach your return line and run it into a bucket and turn the fuel system on and let it hit psi. Then cap it and turn it off real quick. You can buy a fuel valve quick shutoff valve for this or even use the valve from a FI fuel pressure tester gauge with its bleed off valve.

 

[Turdle]

I would not bother with that dye. Just use your shop light and 10 minutes of real thorough lookover in your engine bay at your rails.

This I have done--believe me--over and over,---and even a few times more.
The thought of a leak--FIRE--has me a little paranoid--i even have a little dentist mirror I use for this.

 

[rocket 5979]

This I have done--believe me--over and over,---and even a few times more.
The thought of a leak--FIRE--has me a little paranoid--i even have a little dentist mirror I use for this.

Then you don't have an o-ring leak bro. If your pressure is dropping as rapidly as I get the impression that it is then you would see fuel spraying all over the place if it were an o-ring issue.

 

[Turdle]

I am going to try James' test--with a bucket and cap since the lines are braided.

 

[rocket 5979]

I am going to try James' test--with a bucket and cap since the lines are braided.

Make sure you time things right so there is less chance of a pressure spike if you turn the ignition off too late after capping.

 

[Turdle]

OH
I might mention this--
Fuel pressure I have been referring to, is the reading from my gauge mounted directly into the 1/8 npt port on the front of the regulator--

 

[rocket 5979]

OH
I might mention this--
Fuel pressure I have been referring to, is the reading from my gauge mounted directly into the 1/8 npt port on the front of the regulator--

Thats where I figured you were taking your reading from.