Low Fuel psi warning after FASS

DEEZUZ · Jul 29, 2019

Did a complete fuel system and added a fass and a disaster kit. Now under decent load the dash will throw a fuel psi warning low. But no power issue, no 87 code. Runs great.

STOCK TUNE STOCK TRUCK.

DEEZUZ · Jul 29, 2019

59 psi wot full load and it sets the warning. No cel, just a dash message. Thinking this may be time for a pcm update?

sootie · Jul 29, 2019

59 psi is way to low. 80-120 is normal operating range.

miamipowerdiesel · Jul 29, 2019

when u did the fuel system did u change the fpr or fvc? what was the reason for the new fuel system?

DEEZUZ · Jul 29, 2019

sootie said:
59 psi is way to low. 80-120 is normal operating range.

Spec is 53-73, I think that's on the switch/psi sender side. So we're within that. Haven't done mechanical yet.

. And fuel system got changed cause pump was shedding metal and low frp. Yes entire fuel system.

DEEZUZ · Jul 29, 2019

sootie said:
59 psi is way to low. 80-120 is normal operating range.

Soooo I don't think 59 is way low. 53-73 is spec. IMO anything over 75 is rediculous, keep in mind duramax is getting away with running this pump off vacuum LOL

And fass advertises 55 psi out of this pump.

DEEZUZ · Jul 29, 2019

So mechanical gauge hooked up. 55 at idle and 53 wot. Removed regulator from fass, 'adjusted' the spring and now I'm at 56 wot. With scanner it translates to 71 at idle and 67 wot.. 3 wot blasts and no low fuel psi warning.