Although i do own a Factory Service Manual i left it at my parents house since thats where basically all my tools are... But anyway to my question.

What should be the ideal fuel pressure for a LQ4 6.0L?

What i am getting...
@ Idle: 48psi
@ 2,000rpm cruise: 51-52psi
@ WOT: 58psi

Just seem a little low to me as the last time i rebuilt my old yukon (OBS, 5.7L) it should be more around 60-64psi.

 

those sound about right to me

 

sounds about right for a return style fuel system

 

Thanks for the imput atleast thats something else i wont have to fix hehe.

Atleast my transmission and transfer case is on the list to getting rebuilt come spring time Oh well its what i get for having 75,000 miles already lol

 

58 lbs at all times is what you should be running.

 

now that I look back the 48 psi at idle might be a little low......Have you replaced your fuel pressure regulator?

 

i did a few months ago, before the change the fuel pressure stayed the same all the time. after the change the pressure is 48 at idol, 60 at wot and 58 at 1800 rpm's.

 

Nope still the original regulator on there, If its a simple as a new reg consider it replaced by next week

 

My numbers are higher but, I have the freaky Flex Fuel "Z" truck so the fuel systems are different. I see 62+ at WOT