Quick truck info:
2016 Single cab Silverado
5.3 with 6l80E
25k miles

Mods
76MM turbo
LT4 Injectors
LT4 HPFP
DSX Aux pump
LT2 Intake
LT5 Throttle body
Brisk Boost plugs
3200 Stall

Truck ran great on the dyno, made decent power at 12LBS, made 670. Stayed happy with AFR through out the pull. Ended up with 21 degrees total timing on E70
My dumb *** didn't have the wastegate T installed and couldn't make more then 12LBS, now with it T setup it should make 17lbs

My current issue is the truck is stuttering under boost, as if its loosing fuel or spark. I scanned it and can see the lowside fuel pressure is reporting anything from 3psi all the way to 102psi, its absolutely all over the place. The pulls on the road Im seeing no lean condition on the wideband meaning the HPFP is staying happy. The DSX I believe comes on at 4psi as a result of piggyback into the MAP sensor for the controller.

I did swap out the low pressure sensor and same erratic fuel pressure readings. Before I get too crazy with it by sapping the fuel pump control module out, thinking about disconnecting the AUX pump and see what the pressures do.

Anyone else see surges and spikes all over the place with the low side pressure sensor? Im completely stumped on this one. Right on the verge of just deleting the FPCM and the PWM pump and just run a Hellcat 525 pump with a boost reference regulator and set it at 70PSI

 

hey buddy, i know this is an old post, but did you ever rectify your erratic fuel pressures?

We just installed a new cam with DOD delete on my L83 and it runs fine, but under acceleration the fuel pressures are all over the place like yours, from 10psi to 100psi.

Thanks!

 

I would think either a bad connection or a strange reading from a sensor, causing a falsely commanded high pressure signal.

Do you have any codes?