Fuel system advice

[cfdeng7]

Are the 190s already installed?

If yes, still stock fuel system?

If yes, don't assume the stock pump "crapped out" just yet. I've seen trucks do the exact same thing because the stock fuel pressure management setup is garbage. That pump might be just fine, once you get upgraded lines (increased flow) and proper pressure management installed.

You don't "have to" install a low pressure pump (AirDog or FASS) if you don't want to. You would do that if your budget allowed and you would do it because you want the benefits of the extra filtration and air removal in addition to the offloading of some work from the stock pump.

If I were you, I'd start with a quality regulated return and see what your pressure does then. If you are still having significant pressure issues after that, then look at the pump.

Its still running stock sticks with the upgraded regulator spring from ford, and dozers 3/8" feed lines. I have had full gauges in this truck since I got it over 2 years ago and it has maintained 60 psi at idle and only dropped to 50-52psi at the end of a 0-100 mph run. So it dropping to 40psi at idle and dropping to 25psi driving on the trailer with only 2k on the filters I'm thinking it crapped out.

 

[Strictly Diesel]

Anything else change recently? Tuning maybe? I've seen significant fuel pressure differences with tuning changes (obviously going to hotter tunes).

"Blue Spring" is not the fix many profess it to be. At the very least, swap the regulator spring with an different one and inspect the regulator poppet to make sure it's fully seating when the spring is holding it closed. I'd rather advise you to spend a bit of time (free) first than just assume it's a bad pump (which it might be)....nothing sucks more than replacing perfectly good expensive parts over stupid crap.

Were the filters "motorcraft" or another brand? Have you inspected them since the pressure issue started?

 

[cfdeng7]

Anything else change recently? Tuning maybe? I've seen significant fuel pressure differences with tuning changes (obviously going to hotter tunes).

"Blue Spring" is not the fix many profess it to be. At the very least, swap the regulator spring with an different one and inspect the regulator poppet to make sure it's fully seating when the spring is holding it closed. I'd rather advise you to spend a bit of time (free) first than just assume it's a bad pump (which it might be)....nothing sucks more than replacing perfectly good expensive parts over stupid crap.

Were the filters "motorcraft" or another brand? Have you inspected them since the pressure issue started?

The only thing I changed was adding dozers feed lines about 10k ago. I did the blue spring awhile ago and it was the full kit from ford not just a new spring. Filters are always motorcraft and I pulled the lower filter to see if it looked nasty, it did not. Just now I checked the voltage at the fuel pump and its getting full voltage.Same fuel station I always use, same tuning same everything so I'm pretty confident the pump is bad. It seems noiser than normal as well.

 

[Strictly Diesel]

Sounds like a thorough diag then.