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Discussion Starter · #1 ·
i've got a 2002 lb7 crew cab with 78,000 miles with ally trans performance mods are edge w/attitude, strait pipe, shimmed throttle pedal.

my problem doesn't seem to big but it is a nusiance. every once and a while after taking it easy cruise light throttle etc. then getting on the go pedel hard about midway in the rpms it seems to have a couple misfires quits then continues to accelarate.

have tried all settings on edge incl. complete removal, still does it. run redline 85 plus helps with injector clatter but still happens. checked ballance rates all within +or-2 pump pressure actual and desired readings correct did fuel return balance all within limit change fuel filter every 12,000 miles checked tps sensor no deadspots checked for slippage in tranny only 50 rpm slip max in third gear edge level 5

Im stumped any ideas it's somewhat intermintent so its hard to really track down. any help would be appreciated

thanks smalls:confused:
 

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Discussion Starter · #2 ·
ps injectors and pipes have already been replaced at 34000
 

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Oh...... Squirrel!
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Hi, I'm Earth. Have we met?
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With 40k+ on the new injectors it could possiably be them again as there is no real fix for them but to me it sounds a bit like bursting, coming from either to low of rail psi under power or to much timing, are you stacking the juice with anything, is it a hot juice?
 

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2016 GMC Denali HD 6.6, Leveled, 35x12.5 Ridge Grapplers on Stock Wheels
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i have a similar problem but i have no drivetrain mods at all. at around crusin speed (55-65) its good but if you get on the gas to kick it up to pass somebody it just falls flat on its face for a second or two and then it finally kicks in and goes. does it probly 70% of the time and its only got 30K miles on it. also it does not do it when you get on it from a stop and run it all the way up its fine, just from about 55 or 60.
 

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Discussion Starter · #7 ·
:confused: care to explain this mod? this is the first I've heard of it
It's not really a performance mod, what it is on some duramax trucks gm put to thick of carpet under the go pedal and bottoms out before tps sensor reaches 100% fuel you add shims under the pedal so you get the full travel of pedal kinda luck of the draw if you need it or not.
 

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Discussion Starter · #8 ·
also hooked up the tech 2 at work today during lunch and procceded to rod the piss out of my truck on level five with the edge, got pulled over and got a verbal warning for excessive emmisions:fart but in the procces i think i might have found the problem. luckly had the tech 2 in snapshot mode fuel rail pressure for just a couple seconds was different than the desiered fuel pressure.

pretty positive that its the fuel pressure regulator not a common problem but have seen a few roll through the shop usually caused by rust in the lines, going to install a new one soon as i get some free time and money. will just live with it right now.

thanks for everybodys help
smalls:rockin
 

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Discussion Starter · #9 ·
The only thing I could think of is the factory injection pump is failing or a second pump is needed? :confused:
chances are if i do any more mods to this truck injectors, gt turbo upgrade etc. will a modified cp3 with a dual feed line do the same amount of fuel supply as a dual stock cp3 setup. But like you said you play hard and the allys going to pay planning on upgradeing the clutches before high hp mods.
 
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