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Discussion Starter #1
Been to diesel shops and short of just throwing a bunch of money at the truck kinda dead in the water

The issue I have with the truck is if I drive down the road it runs fine, when I leave the truck idle after driving it acts is loads up, won't go over 1800 rpm smoked like a chimney.... If I hold the pedal down it smokes clears up runs great!!!

All my injectors are in great shape +-1

I read two codes
P0401
P0404

Things I'm noticing with truck is this, when I pull up to idke my turbo vane sensor will go to 0 percent when the computer is asking for 87, it will set there for a moment throw those two codes jump up to 100 percent and then rest back down to 87 percent.... Stumped to why it wouldn't be throwing any sord of turbo vane position sensor code or anything along those lines....

Any ideas?

I am not running a programmer just insight cts


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Those are EGR codes
 

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Discussion Starter #3
I know they are EGR codes... Which egr is not whats causing the issue


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Have you cleaned maf. Egr could be stuck open. Can you hear the turbo veins sweeping at idle.


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Discussion Starter #5
Yeah I've cleaned the maf nothing out of that, I didn't replace the egr but I took it out soaked it over night cleaning it, at idle the turbo doesn't sound like it changes and I hear no different tones in exhaust, if I clear egr codes it idles up then down like its suppose to until the turbo reads 0 and trips the egr codes... I also took a egr from a buddies truck and swapped it out and same thing same codes, from my understanding running 4 inch turbo back would cause egr codes also right?


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Discussion Starter #6
Only other issue I know about truck is my horrible mileage I can't get over 13 if my life depended on it highway city stay out throttle anything


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egr valve might be sticking
 

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On lly with fe9 in glove box it will not trip the light.
 

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4 inch exhaust
 

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On lly with fe9 in glove box it will not trip the light.

Yes, my lly with fe9 won't throw a light with 4" turbo back and egr blocker plate.
 

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Hes talking about the emissions your truck is equipped with. If u block the EGR and fingerstick or remove the cat and add exhaust the CEL light wont come on with a FE9 Equipped truck. It will set the light if it notices something wrong with EGR no matter what emissions it has. The EGR works off the back pressure of the exhaust.
Is EGR blocked and sticked?
 

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Yes, my lly with fe9 won't throw a light with 4" turbo back and egr blocker plate.
It won't set a light but it will still set and store a code in the pcm
 

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Discussion Starter #14
No egr is no blocked and sticked, I wanted to do a full egr delete kit and go to efi live... Haven't made that jump since the truck isn't running right...

Didn't want to spend money on a that if I needed to spend money to get the truck running again... I know I've got the egr codes... But what's causing the vane sensor to read what it is? If something was sticking its suppose to throw a code which it's not... And even with a full functioning egr in the truck it still a ya up....


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I would look into the problem with the vane sensor.
Try to find out what the readings are supposed to be at idle.
Duramax's are new to me ive worked on Fords for 20 yrs. The linkage on the variable vanes on a Ford 6.0 would wear out causing the vanes not to work.
I have a fleet of Duramax's now havent encountered that problem.
I will look up on All Data tomorrow and see what the tests are and check back.
 

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They are saying your egr is crap. Delete it and fix your problems.
 

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Discussion Starter #17
It's asking for 87 percent at idle... When truck goes to idke it dips down to 0 percent which us when it throws the egr codes then it goes to 100 percent then it will go it 87 percent and sit there...

Even if my egr is junk... The truck does the same exact thing with a perfectly good egr installed... So that tells me it is not the egr


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I would look into the problem with the vane sensor.
Try to find out what the readings are supposed to be at idle.
Duramax's are new to me ive worked on Fords for 20 yrs. The linkage on the variable vanes on a Ford 6.0 would wear out causing the vanes not to work.
I have a fleet of Duramax's now havent encountered that problem.
I will look up on All Data tomorrow and see what the tests are and check back.
The turbo on a 6.0 and a duramax are the same turbo only diffrent is the duramax is cooled with coolent and oil, 6.0 is cooled by only oil

And the linkage ur talkin bout is the unison ring, I don't like that design at all
 

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Discussion Starter #19
Is there any type if lag time to throw a code? Like if something sticks is there a certain period of time it has to stick for to throw a code?


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Is there any type if lag time to throw a code? Like if something sticks is there a certain period of time it has to stick for to throw a code?


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Those codes are not from your turbo, they are EGR codes (likely set by your exhaust and missing converter).

To fix it get yourself an EGR blocker plate or EGR delete and install EFI......after that, no more codes and MPG comes back.
 
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