History on truck:

2003 Excursion with the 6.0. Headstuds, egr delete, blue spring, fuel filters, 4" turbo back, RiverCityDiesel tunes on a SCT x3. Heads were replaced at the same time as all of this other stuff - it was done last summer.

Noticed in fall after putting the hotter tune on the truck, that at WOT, the truck bucked and ran rough. Does not do this with the 'street' or the 'tow' tune. Never really run the hot tune, so I tossed the 'tow' tune back on it and have been driving it ever since.

In November or so, I could hear a faint whining noise. Late January and it is much much louder, and was able to track the noise down to HFCM/Fuel Pump.

Last week I started the truck - without having it plugged in all night - temps were ~10F. Hopped in after 30 seconds of idling and drove it down the road. A few miles out of town, it 'bucked' a little bit, and I started loosing speed and RPM. Eventually came to a crawl and the truck completely died. Sat there and scratched my head for a bit and tried to start it again - oddly enough - it started up and got me the rest of the way. Have really not driven it at all since then.

This morning, needed to drop the kids off at daycare, - again forgot to plug it in last night. Temps are ~15*F. Started truck and left it to idle in the driveway. After a few minutes, it sounded like it 'idled down' a little, and then sounded like the idle was hunting around, so I went outside to investigate. Got into truck and tried to bring RPM's up a little a few times, and both times it chugged and about died. Turned the truck off, came inside, and here I sit typing this.

Fuel filters have around 6k on them.
Oil is due to be changed in about 750 miles.


Do these issues sound indicative of a failing Fuel Pump? Trying to think of anything else that could cause same symptoms.

Have searched and searched, and came up with a few similar threads, but nothing concrete.

Help!

Thanks!

 

Additional info that I forgot to include:

Also used 16oz of the white powerservice for a full tank of fuel about 3-4 days before I ran into the issue where it lost power & rpm and died on the highway on me. I dont think this is related - but wanted to include in the info just in case. Still on the same tank of fuel - about half full.

 

One more update -

The HFCM/Fuel Pump noise is not a 'constant' noise. It sounds 'jumpy' if that makes any sense.

 

Hook into the upper filter port and find out what pressure you do have, no sense in guessing. Not sure about what tunes you run but in the Winter I revert back to stock for the cold engine strategy.

 

Mine recently went out. I opened the upper fuel filter and had my wife turn on the key and no fuel pumped into it. I was told by a member on here that it should fill up very fast. Thats what I went on and replaced it and all is good now.

 

Thanks for the reality check.

Fuel Pressure gauge ships tomorrow. In hindsight - I really should have had one by now.

 

What was the outcome?

 

Sorry about the late update.

Replaced Fuel Filters - HFCM is no longer loud.
Fuel pressure gauge is installed - here are the results.

Idle: 56-58 psi.
Cruise: 54-56 psi.
WOT: under 45 psi. I lifted when I saw it drop that low.

I do have the blue spring upgrade as well as the banjo bolt change.

Not sure where to turn from here. Assuming since I already have the blue spring, a new HFCM is in our future (before towing season.)

 

What brand of fuel filters did you install? Non-OEM filters can cause a fairly significant loss of fuel pressure. Are you running a tuner?

 

Motorcraft filters, and yes... I do run a tuner. SCT X3 with River City Diesel tunes.

Currently have the 'street' tune running which is their 'basic' tune. Have not tried running with the 'race' tune.

 

I'm willing to bet that if you go back to your stock tune you won't have fuel pressure problems at WOT. If you do then it's time for a pump. Regardless, the pressure is low for what I've seen with most of the blue spring upgrades but not critical. I prefer a little more fuel vs. a little less pressure.

 

That's what I was afraid of. How in the heck can people run big tunes and get away with it? Stock injectors of course. Just would like to be able to run these tunes.

 

Very good question!

 

Ask to see the Dyno sheet on their big tunes... I milk the injectors on 425HP at the rear wheels.

 

I've seen claims of people running "big" injectors on big tunes with the stock HFCM and still maintaining fuel pressure but I could never do it even with only 155 cc injectors (stock are 135) on the tunes I was running. Either their tunes aren't what they think OR their injectors aren't what the injector builder claims (more likely).