2004 E450 FPR - y/n?

I'm finding conflicting info on whether our 2004 E450 6.8L V10 has a fuel pressure regulator. 

I just called the dealer parts department, gave him the vin, and he said it does. Unfortunately he didn't have a diagram to show where it's located. 

However, when I search online I'm seeing that 2004 & up has a returnless system & no FPR - it controls pressure through varying the pump. 
 

I checked Advance/Autozone/Oriley/Napa - Advance doesn't show one for 2004, but does for 2003 & prior. The others all show one for 2004. I'm picking up an FPR from Oriley's after work, but there definitely isn't one mounted on the fuel rail on the engine, so I have no idea where else it would be? 

I have no idea about that model, but they're often in the tank right next to the pump so that might be worth investigating. 

If my memory serves correct yours should not have one. 

In reply to Tom Suddard :

I sure don't remember seeing one when I replaced the fuel pump & the 2 vent valves earlier this year.

In reply to Professor_Brap (Forum Supporter) :

Thanks! 

Probably a dumb question, but if it's returnless, would there still be 2 fuel lines connected to the fuel rail? I'll have to pull the console again, but I'm pretty sure I saw 2 different connections & I think the fuel pump had 2 connections on it too. 

Looks like I answered my own question. I pulled the console & checked again. There's only one fuel line running from the back, which goes to the fuel pressure sensor, then splits toward each fuel rail. 
 

However I noticed something odd looking when I took that pic. What is this gaping hole that's partially blocked by the passenger side head? I presume it's supposed to be like this?

So I'm picking up a new fuel filter tonight. I have doubts that will fix the problem. Unfortunately I'm also having difficulty finding someplace who will work on it, because if the filter doesn't fix it I need to find/pay someone who can get it done asap.  

The hole looks a bit like where an EGR valve would mount, but if you don't have a horrible vacuum or exhaust leak, don't worry about it.  Probably an unfinished part of the casting.

What original problem are you trying to solve?

Unused port on the head, one size fits all gasket.

No regulator, fuel pump is pulsewidth controlled by the PCM.  The data if you have a scan tool is non obvious, the percentage is halved - 50% duty cycle in the data list for the pump is 100% drive.  75% means something that I forget what...

In reply to Pete. (l33t FS) :

Thanks!!!

I'm using Forscan. It was showing 104-106 kPA at idle(which I think is about 15psi), and when I revved it a bit in neutral it drops to 90 kPa, bounces up to 120 kPa, then settles back to the 104-106 range. 

In reply to Streetwiseguy :

The problem started when I took it for a test drive Saturday night. It started out running just fine, then got a slight miss that seemed to kinda clear up as I got on it, but a couple miles later it wouldn't accelerate at all, and by the time I got back home it was barely running. This was over about 7-miles total, of 20-55mph speeds. 

I replaced the fuel pump earlier this year, along with both fuel tank vents, but only took it for a couple short drives since then. The last being on 4/2 prior to Saturday. 

At first thought, I'd say you need about three times as much fuel pressure.  Most vehicles are 3bar, which is 300kpa, which is 43.5 psi, or thereabouts.  I think. 

There are some 60 psi units out there  too.  

Can you read fuel pump duty cycle?  Like Pete said, 50% is about max they want to see.

My 2017 E-450 6.8 has the gasket exposed on the passenger side intake.

In reply to sergio :

Thanks, that's reassuring. 

In reply to Streetwiseguy :

I believe so, I'll plug in again tomorrow & check what signals are in the PCM list. Thanks!

What brand was the new fuel pump? If Airtex that's the problem.

In reply to TurnerX19 :

I initially bought a Carquest one that was DOA, so I returned it & got a Delphi that's in it now. 

Fuel Pump Driver Module. We used to replace them in droves on the E and F series.

In reply to kevinatfms :

Ooh thanks - I'm not familiar with that, but I'll check it out!

Pete Gossett (Forum Supporter) said:

In reply to kevinatfms :

Ooh thanks - I'm not familiar with that, but I'll check it out!

They are located on the driver side frame rail just aft of the drivers door but before the tank.

The new one comes with longer bolts and spacers so the corrosion won't bend the circuit board when the back rots off.

In reply to kevinatfms & Streetwiseguy:

Thanks! I picked one up at lunch. It looks like it's near the fuel filter, so I'll get both changed out(probably not until Saturday) and see how it performs. 

I'll plug in tonight & get the fuel pump duty cycle numbers. 

Fuel pump duty cycle shows 49% regardless of throttle position. 

Fuel pressure is mostly staying in the 104.1-105.3 kPa range, though it briefly dropped to 103.x  

Fuel pulse width 1(cyl bank 1) was bouncing between 5.72ms & 6.35ms, but seems to have settled around 7.41-7.92ms now. Fuel pulse width 2 seems a tad bit tighter, between 5.78 & 6.23ms, but  is in the 6.87-7.32 range now.

Cam position sensor just shows "Low" mostly, but occasionally goes "High". 

Fuel pump monitor seems to be toggling between On & Off about every half second. 

Anything else I should check?

The fuel pump is dead.  49% means it is driving the pump as hard as it can and it is still not able to generate enough flow/pressure.

That 49% means it is running the pump 100%.  Told ya it is a little screwy.

There is a chance that there is merely a huge leak in between the pump and top of the sending unit (have seen rubber hoses split before) but either way you are pulling the sending unit back out with all that entails.

It "could" be a bad fuel pump module, but I have never seen one sort-of work.  They work right up until they don't, usually during a rainstorm. The water gets in through the deeply corroded housing.

In reply to Pete. (l33t FS) :

Ouch. Interested in an all-expenses paid "vacation" to the coast to replace the fuel pump? :-p

Edit: Any recommendation on which brand fuel pump to buy?

Pete Gossett (Forum Supporter) said:

Interested in an all-expenses paid "vacation" to the coast to replace the fuel pump? :-p

Well I guess this is now a serious offer to any capable GRMer... There is not one single place here that will touch an RV. The dealership doesn't work on RVs, Camping World doesn't do mechanical repair work, the local Diesel shops won't touch it because it's a gas engine, the mobile truck repair places won't work on it, and neither will my regular mechanic. 

At this point I can no longer worry about what it costs, I just need it fixed ASAP before a big storm decides to head our way.