Fuel pressure numbers....

[cajunpsd]

Installed gauge yesterday..at idle 63-64 psi..made a couple wot runs..truck is at a loss of power and pops/sputters at 3/4 to full throttle..fuel pressure went down to 40-41 psi..is fuel pump my problem? I have had 3 injectors replaced last year. Truck ran like crap until It warmed up..fuel mileage is down also..

[RRF985]

Lack of fuel is your sputtering problem. Anything below 45psi is bad for the injectors and is probably why you had 3 go last year. If you haven't already, get the upgraded blue fuel pressure spring in your truck immediately. That should fix your problem. If you already have done the blue spring, it's time for a new fuel pump IMO.

[thomaslord84]

Have you done the fuel psi regulator upgrade from Ford? It is known as the blue spring mod. If you haven't done it already go to your local Ford stealership and ask for the updated fuel psi regulator kit. It comes with instructions. If I remember correctly its about $50.

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[thomaslord84]

RR beat me to it.

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[cajunpsd]

That was my thoughts also..just wanted confirmation..I will stay off the skinny pedal till the blue spring kit comes in..hopefully no injector damage..it just started the sputtering about a month ago..will keep y'all guys posted on outcome.thanks todd

[DoubleDpsd]

I was dropping to 20psi with my old pump, NO sputtering or loss of power and that was with spd+herc. Who knows how long I had been doing that before I installed the fuel psi gauge. truck still has stock sticks. 40psi is low but my fuel pump was worse off and I had no sputtering or loss of power dropping to 20psi at WOT with spd and herc, fwiw. If fuel mileage is down I would venture to guess that's a culprit of injector issues imo. I don't see how a blue spring will eliminate any sputtering/popping but I guess it can't hurt.

[thomaslord84]

Originally Posted by darsey715

I was dropping to 20psi with my old pump, NO sputtering or loss of power and that was with spd+herc. Who knows how long I had been doing that before I installed the fuel psi gauge. truck still has stock sticks. 40psi is low but my fuel pump was worse off and I had no sputtering or loss of power dropping to 20psi at WOT with spd and herc, fwiw. If fuel mileage is down I would venture to guess that's a culprit of injector issues imo. I don't see how a blue spring will eliminate any sputtering/popping but I guess it can't hurt.

You are correct in that the pump may be going out. The FPR spring may also be weak. The blue spring is a lot cheaper than a new pump and that is where I would start. If after the blue spring fuel psi was good and it was still sputtering, I would test ficm and get a contribution test done. My point is to start at the cheapest and work your way up to the expensive.

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[cajunpsd]

Blue spring on its way .. Contribution test was what I couldn't remember.i need to find a local reputable shop that can do it..stealership not an option!!

[thomaslord84]

Yea I would not let the stealership do mine either.

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[DoubleDpsd]

Originally Posted by thomaslord84

You are correct in that the pump may be going out. The FPR spring may also be weak. The blue spring is a lot cheaper than a new pump and that is where I would start. If after the blue spring fuel psi was good and it was still sputtering, I would test ficm and get a contribution test done. My point is to start at the cheapest and work your way up to the expensive.

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my guess is that it ISN'T the pump since it's holding pressure at wot. my guess is it's another injector issue.