Well... I think I have a Fuel Pressure Problem...

[jrtcbmw]

Ok, so for the past 2/3 months I have kept telling myself that I have a fuel pressure problem, but haven't had any normal symptoms. Until recently has a more defined symptom arose.

Back story/vehicle history.

Truck is tuned and has studs and all the know issues fixed. (FICM replaced, failed injector replaced, regular maintenance done, OEM/Racor filter, Synthetic oil, etc).

Biggest thing done was the Ford Blue Spring. That was replaced when I did my headgaskets/stud back in April 2011. I think i put the Fuel Pressure Gauge on back in January.

Pressures were decent. 65psi idle, 58/55ish WOT (Figured they were a little low due to old fuel filters, at the Jan time frame had about 3k or so before they were due. and from my dealership/tech experience i know as filters age pressures can drop and changing filters can and will fix some driveablity and issues with trucks from time to time. so i figured the lower pressures were due to my filters, and that i had no real issues/symptoms)

Well last weekend replaced the filters, no change in pressures. So at this point I think its just the truck.

I finally had a chance to go WOT 3 nights ago (on a road i know i can go threw the first three gears before i let up)

I was watching the pressures, and noticed my idle was down around 62/63psi. Jump on it 1st and 2nd gear i was down at 50/51psi. Shift into 3rd gear, all of sudden my pressure drop to 30psi. Instantly i let up. coast down in speed. figure maybe a fluke or something.

Next night did the same thing, but this time stayed in throttle longer in 3rd. sure enough dropped and stayed at 30psi. let up to save the injectors.

So tonight i make a 3rd attempt, hoping that i was just seeing things and this time once 3rg gear hit, fuel pressure dropped again, except this time went WAY down, down to 20psi. Let up and coasted and drove easy all the way home.

So now I know i have fuel issue. and I just want to see what the ORG has to say before i begin my diag.

Thanks in advanced,
Jason


Cliff Notes --- properly maintained truck, new fuel filters, shifting to 3 gear under WOT FP drops to and under 30psi, ORG's thoughts

[Brieldo]

HFCM on its way out?

[jrtcbmw]

That's what's I was thinking before the "symptom" showed up. That my HFcm was getting week or I had a fuel pump getting weak

[Brieldo]

Originally Posted by jrtcbmw

That's what's I was thinking before the "symptom" showed up. That my HFcm was getting week or I had a fuel pump getting weak

That'd be the direction I'd be looking in.

[jrtcbmw]

Originally Posted by Brieldo

That'd be the direction I'd be looking in.

Thats where im looking at this point. My concern was the fact that it only happens in the 3rd gear shift. Granted i never got above 3rd gear to find out if it happens in upper gears. but the fact that its one gear has me really thinking.

Now the real question is, replace with OEM or Aftermarket upgrade...

[scparrish]

hfcm time for fun upgrades

[DoubleDpsd]

Mine does this, when the trans isn't in limp mode. I had been driving it around without a fuelpsi gauge and it must have been dropping to 20psi often but as soon as I got the gauge I stopped digging on it. Mine was the same, as soon as it got to 3rd while wot from a stop it would plummet to 20psi. fuel pump going in with new trans.

[jrtcbmw]

Looks like i may be doing the AirDog sooner then i planned...

If i go that route which AirDog do i get and do i need the sump too?

[DoubleDpsd]

airdog II and yeah I would recommend a sump. reminds me I need to get a sump also. good luck.

[jrtcbmw]

Thats what i thought about the AirDogII

I just dont know how i feel about the sump though, first off it will take in more dirt in the tank and 2 i dont know how i feel about something hanging below my tank and if it will even fit with the tank skid plate.

Wouldnt the Strickly Diesel fuel pick up kit do the same as the sump? or at least allow for more fuel to be picked up? (http://shop.strictlydiesel.com/store...ig_Tank_Pickup)