The only other screen I know of is the sump tube screen at the bottom of the fuel tank. I actually don't see squat wrong with your fuel pressure dropping to 45@WOT. I wish mine would stay that good.

 

I'm in no position to argue that. I was just trying to be helpful with some information I was givin. I would have thought that 45 was good also but my guy told me that was the MINIMUM recomended by Ford and you are getting close to hurting the injectors at 45psi.
May be a little over kill.... I don't know. I would suspect someone may be able to tell us for sure

 

If it's holding 55/56 at idle then it isn't the regulator, which is nothing but a spring anyway. Think of it this way. The spring is holding your fuel pressure at "X" psi. Anything over that gets returned to the fuel tank or wherever. Once the pressure starts to drop from demand by the injectors then the spring shuts the relief valve until it gets back to it's "set" level which in your case it 55/56 psi. putting a ball in the spring will basically only raise the pressure at idle. It won't give you more fuel at WOT. The pump is only going to pump so much fuel anyway. Once it reaches it's limits the pressure is going to drop and won't come back up until the demand is reduced, which in this case is letting off the throttle. The only other explanation would be trash on the tank pickup screen or a restriction in a line somewhere.

Did that explanation help?

 

I got ya... Makes sence now.

Sorry Bismic...... Didd'nt intend to

 

No problem!

 

The diagnosis is in ................... 52 psig idle and 49 psig at WOT. Looks like my gauge (or sending unit) is way off and so is my tire pressure gauge. Time to call Nordskog I guess (I hope they are not out of business). I guess this is good news. I went ahead and had the tech apply the latest flash. Hopefully it is truly designed to be easier on the FICM. I sure do like my tech! He sure liked all my filters (coolant, powersteering, ccv).

W_huisman - you have a pm.

 

In all honesty, if it was me I would actually prefer that scenerio to the one with having a bad fuel pump.

 

You are absolutely right Evan. I was feeling a little upset that the EXPENSIVE sending unit and gauge combo could be THAT far off. I should be glad that I haven't been hammering my injectors!

 

How old is it and what is their warranty policy? If they are still around they might be willing to work with you(most companies with good customer service would be willing even if you are a little bit past warranty).

 

PM back, Mark.

Maybe I need the latest flash too?

 

I had my truck at the dealership this week because I got a p0611 code the other day.

Ive had fluxuating fuel pressures non-stop with this truck since buying it and putting the fuel pressure gauge on it last spring, but I had installed the BB mod to keep pressures above 45psi and was getting by, with pressures fluxuating anywhere from 62psi to 47psi. Prior to that I had installed a new HFCM and installed a new nordskog sending unit for my fuel pressure gauge trying to correct the problem out of my own pocket.. Both made little difference.
The final straw was seeing the P0611 code pop up a week ago. I pulled all my gauges and coolant filter, uninstalled the bb in the regulator, and reinstalled the cat. Then headed into the dealer.

The dealer did nothing more than install the latest pcm, ficm, and tranny flashes. They said that everything else checked out fine after doing that, so they stopped there but said to immediately come back if I have any more issues. Didn't cost me a penny.

Reinstalled my gauges this morning and IMMEDIATELY noticed a SOLID 50psi at idle. Hooked up the boat (4000lb), went for a spin, and couldn't get the pressures to drop lower that 47psi!

I AM ABSOLUTELY TICKLED!

LESSON: If your fuel pressures are fluctuating by more than 5psi and you're not sure if you have the latest flashes, GET IN TO THE DEALER!

 

w_huisman -

THANKS! As I said earlier, I had my truck flashed at the same time I had him check the fuel pressure. I have not yet re-connected my fuel pressure gauge. I will go do that this evening. I hope it works!! Tim (npccpartsman) gave me some very good suggestions also, I just have been to lazy to get to them yet (maybe he won't read this).

 

I bought a new tire pressure gauge. Verified it against my air compressor pressure gauge and the tire pressure gauge at the local Shell station (had a flat spare tire). Using this pressure gauge, I read 52 psig at the fuel filter test port. I feel better now.

The bad news ...... I finally tried the tips provided by npccpartsman and no luck. It just appears I have a bad sending unit OR a bad gauge. I am betting on a bad sending unit (or at least it was calibrated for different voltages).

Hopefully Nordskog will make good on this. Regardless, I will be changing to Isspro.

 

The engineers at Nordskog told me that the pressure curve of their sending unit matched the one I had from egauges. So I have always presumed that a 5 psi drop on my egauges sending unit would also register as a 5 psi drop on my Nordskog unit.

What they didn't tell me was that it would read 13psi lower than actual.

I have an calibration adjustment in my Commander to compensate for this, luckily.

Are you saying that you don't believe a 1psi change on the Nordskog unit = a 1psi change on the egauges unit?

 

Where is the spring located for the fuel pressure?