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Discussion Starter · #1 ·
long story shortened
04.5 LLY 211k purchased w 160k second owner older guy owned had a bed slide in it at one point a 5th wheel its mint in and out and records drives great nice and tight been taken care of so it seems

i got it as a transport / work truck it was having heating issues did all the LBZ mods on intake race valve straight pipe tune is soon to come cleaned radiater ect now it doesnt get hot

but its got a little surge / hick up at idel sometimes then it would go into limp mode clear codes and it would drive then be weak on power the turbo went i just put a new turbo in fuel rail pressure is all good but it just went back on road went into limp mode rough idel and had no pedal cleared codes it was ok any ideas i dont have the codes had to do the turn key open door its like its starving for fuel the codes in past were low pressure to fuel rail and fuel pressure regulator possibly air getting in fuel lines or being starved of fuel and when it does the hick up it will puff a little smoke
 

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1st, here's a box of periods....................................................try and make some sense of a pile of words. :rolleyes:


Limp from what? There's more than one source/type.
 
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Discussion Starter · #3 ·
low fuel rail pressure and fuel pressure regulater codes

also fuel filter had black shit in it
 

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The Black is the normal fuel solids filtered out. Refining processes nowadays gives us unstable fuel, with a short shelf life, about 6 months. While it's possible to fill up with some poor quality fuel, the truck's fuel system can also be our fuel's worst enemy, with the constant unused pressurized heated fuel returning to the tank in a loop.

Thru this breakdown process, you wind up with a coating on any surface throughout the fuel system. Non-use storage/occasional driving doesn't help with the decaying fuel. Certain fuel additives can help to stabilize and clean.

All of the above, in regards to a lack of use for it's age vs mileage. Your use of the truck now is going to start waking up some of the demons lying in wait, which can lead to shorten filter lifespan as the solids break loose and are caught in the filter.

B10/B20 fuel use is good for it's lubricity values, but with that comes a solvent action that can quickly clog up a fresh filter as those 11 years of solids are dissolved. Use of higher bio level fuels on a regular basis keeps it cleaner and lubes things up, but if it sits awhile from non-use, the bio has a higher attraction of water. Additives in this case can help (proper and proven brands).

Fuel lines decay as well as the internal seals in the fuel filter head, which can lead to loss of prime, excessive aeration of fuel, lope at idle, and/or a no start.

Fuel Limp = P0087
What is/are the current DTC codes? If you can clear 'em, you can read 'em. Most any AutoParts store will pull the codes if not.
Is it a true limp or a FPR issue? We need more info on those codes.

Fuel supply issue; it could be as simple as a clogged fuel filter, or the filter head itself cracked or leaking, old cracked/split fuel lines at the head sucking air, kink/collapse at one of several bends in the flex hose sections of the fuel supply lines, or a cracked/leaking fuel sending unit at the tank, or the FPRV is old and leaking by, or....

Did changing the fuel filter make any difference?
Do you have any way to check fuel pressure aft filter head?
Do you have access to a scanner that can data log actual vs desired fuel rail pressure?

That's ^^ all a lot, let's pinpoint it down.
 
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Discussion Starter · #5 ·
changed fuel filter 3-4 times in last 50k i have a cat one w adapter at the shop that is going on as soon as the truck gets back then ill read and post the codes its running ok now so it seems to be intermittent i dont drive the truck i will be now more however but my driver said it got worse when he changed the filter last out in cali its when its hot it acts up or if it sits at idle for a while then acts up have to shut down wait and restart
had it hooked to tech 2 at dealer all fuel pressure was normal he recomended replacing all injectors and glow plugs and turbo i did the turbo since it blew up but i dont believe it has injector issues

we had it at ppe in cali and they didnt think so ether
 

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Discussion Starter · #6 ·
i have a list of codes i pulled

u1255
u0101
b2600
c0035
c0040
p0087
p1093
p1094

i have an autocal is all...
 

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Changing filter 4-5 times in the last 50k....that's not necessarily excessive. Don't do the cat/adapter, you're going the wrong way, not improving.
Did you ever change the fuel filter for new, in dealing with current issues?
If you did, was the filter full of fuel or half empty?

1st 5 are all communication loss codes. Can be from low voltage (batts bad and/or run down from excessive cranking), or a wiring issue. Mouse damage visible? Harness chafing in & around the boost tube?

The last 3 are all fuel supply errors...having probs pulling fuel. Could be clogged filter (checking incoming pressure aft filter would help), sucking air from leaks or cracks in the filter head or the supply lines there, clogged supply pickup in tank, cracks/leaks with the sending unit assembly there, bent/collapsed fuel lines, faulty FPR, or the FPRV is leaking by.

Search 'bottle test' to check FPRV for excessive fuel returns.
 

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Discussion Starter · #8 ·
Just put new battery's in it sat for a while when it was getting turbo done so that would explain those

One of the guys put a tank of gas in it we drained flushed changed filters ect due to that but truck was never turned over so no gas got in motor then it was having issues a while after that he took truck to Ppe in Cali they did filter race valve ect but now it's surging at idle I'll try that test next
 

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I am having issues with my LLY as well. Here are my codes after replacing MAF, MAP, Alternator, Fuel Filter, Air filter, and testing my new batteries. Anyone else have this problem?
Rectangle Violet Font Magenta Circle
 
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