Joined: Feb 2018

Posts: 41

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look for some input to point me in the right direction before i just start pulling stuff apart i have a 2012 GMC Sierra 1500 5.3 with a s475 Turbo the truck got dropped off to be dyno tuned yesterday and i got a call from them saying that at 6000 rpm the truck goes from 58psi of fuel pressure down to 38psi I’m running a walbro 450 with 88lb injectors we made 554rwhp on 15.4 of boost wondering if the factory wiring harnesses could be to blame or also wondering if my fuel pressure regulator location is to blame i know you want it as close to the rail as possible it is currently mounted on the frame rail under the driver door it has about a 2’ line from the regulator to the rail any input would be great thanks

Joined: Nov 2015

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Joined: Feb 2018

Posts: 41

Likes: 0

The battery

Joined: Jul 2004

Posts: 19,007

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From: Western PA

Joined: Feb 2018

Posts: 41

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Yes it is

Joined: Feb 2009

Posts: 7,741

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From: Detroit

Joined: Feb 2018

Posts: 6

Likes: 1

Any progress on the fix? I’m having the same issue.