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‘05 LLY reg cab longbed (farm/hauler)
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Discussion Starter · #1 ·
Hello All,

the LLY project truck got put on hold and havent had a car for the last year so the farm truck LLY has been my daily through COVID.
Last weekend i was getting ready to take a trailer out to look at a car and it acted like i hit a false rev limiter at 2000rpm.
Shut down the truck after limping it home and tried to diagnose.

Symptoms:
Runs fine for 5-10 minutes then after pushing it hard it will hesitate and then max out at 2000rpm.
A little puff of smoke right before 2krpm
What sounds like injector rattle when i let off
Turbo sounds like it is pushing boost just fine, no odd sounds there.

What i have tried/already had done:
Turbo MP - ebay style
Fuel relief valve shim kit yesterday
Fuel filter yesterday
Double checked my EGR block off as it acted similar when the EGR went bad, but with more smoke
Checked all harnesses that i could. nothing seemed wrong there
Injector Ice pick was done right after i got the truck

The truck has never had a tune on it to the best of my knowledge. bought it at 130k miles and it is now at 184k.
again, i havent seen any codes or CEL during all of this, but i do only have a very generic scan tool.
Would you guys and gals have any ideas on what to look for?
 

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im having the same issues as you are with my lly,i have checked all of the stored codes.the only code i get is low fuel rail presure upon power enrichment.limp mode from low fuel rail presure.i have checked and replaced every thing on my fuel system except the fuel pump and injector pump.i did have an injector with problems and i heard that that problem can pop the presure releif valve.these things are junk.they are already the weak link in the fuel system.i will be trying my new presure relief tomorrow.
 

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‘05 LLY reg cab longbed (farm/hauler)
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Discussion Starter · #3 ·
I ordered a filter head rebuild and a full plug for the fuel pressure relief just to be sure.

I’ll also be running it down to a local shop to check balance rates, fuel temp, and rail pressure.
I’ll post again when I get that info. Thanks all
 

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‘05 LLY reg cab longbed (farm/hauler)
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Discussion Starter · #4 ·
Hey guys, bottle tested again yesterday and had an oz or so in the bottle. Going for the plug this week. Will update again then
 

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well the presure releif was a flop.still limps when i put the pedal down.it feels like its running out of gas when i hammer down on the throttle.let me know how the plug kit works im thinking on the same thing
 

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Allis20 - when you are at the shop, have them check the MAF and MAP sensors for a reasonable reading, about 40 g/s +-5 at warm idle in park. MAP should be about the same as BARO, about atmospheric pressure for your altitude. These are critical for the ECM to deliver correct fuel to the engine.

Also, search for '2000rpm' (2000 rpm, etc and similar) as there are several other posts with similar symptoms
 
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‘05 LLY reg cab longbed (farm/hauler)
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Discussion Starter · #7 ·
Hey Ron! Thanks for the info! Just waiting on the plug and if that doesn’t fix it I’ll run it down to a shop where I borrow their solus scanner.
Mine won’t go any further than basic engine data. Yeah I dove through a bunch before posting and they all seemed to say fprv or cp3 so I started there.
Thought the fprv shimming would fix it but maybe I scratched the end cap when I installed it or something.
Thanks again for the info I’ll add on after Wednesday!
 

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Check fuel lines next to fire wall on drivers side. They collapse
 
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‘05 LLY reg cab longbed (farm/hauler)
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Discussion Starter · #9 ·
Hey all,

to come in and close the topic, shimming of the fprv helped but didn’t fix it. Installed the full fprv plug last night and the truck is back to running perfect. Thanks all for the help!
@papastruck05
 
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