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Discussion Starter · #1 ·
Hello all,

I've been having a ton of issues with my truck and have spent substantially more money trying to fix it than I would have ever liked.

These issues started just before I deployed at the end of 2019. The truck ran low on fuel and the truck started misfiring like crazy: p1242, p1239, and another injector code. Injectors were replaced and the truck drove fine for a few days when I got back from overseas. They started to slowly degradate though. I would never get a misfire in the morning, but would start to get it on the way home from work. Clearing the code would return the truck to normal operations. I would have to clear it once a week, then once per drive, then multiple times a drive, and then the code would instantly come back after being cleared. Injectors were replaced again. Same thing happened again. Issue was fixed, then periodically came back, then daily, then multiple times a day, then it can't be cleared. Strangely, it still would not happen in the morning until it got to the point where it could go longer be cleared

The shop now believes that there is an issue with the ECM and tune. He believes the drivers for the injectors were dropped out of the ECM. Does this sound possible? If so, can someone point me in the right direction through PM on who I can contact to tune my truck? I also have EFI live V2 that I've never really used.

Truck is a 2008. It has a DSP5, 100 overs, custom built transmission, air dog 2, dual cp3, aftermarket single, deletes, etc.

This has not been a fun experience... if I knew all this would play out the way it has, I would have sold the truck as is before deploying and bought something new. This has been a complete nightmare. Any help from you guys would be really really appreciated

Brett
 

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Some thoughts I have:

-Did they send out your old injectors for testing and confirm they were bad? (hopefully this is a yes).
-IF previous was a yes....then its possible that the injectors are bad again due to outside influence (assuming the same outside influence that occurred with the original). Debris or something. how many miles on the new injectors?

I really question if its the tune as they suspect honestly, as the tune will not change over time. The sensor inputs could that drive the ecm's math, but the actual tune is a set calibration.

Take that V2 and ensure you save down your current tunes before even thinking about flashing though just in case. EPA has cracked down as you know and getting a tune to support your lack of smog parts is going to be a real task nowadays.

SO if you have ensured you have no harness problems to those cylinders (no chaffed wires or shorts)....its possible its an ECM problem. I just question its change over time, BUT electrical can be very sporadic for no conceivable reason. if you decided to do a new ecm....you could install your tunes onto the new ECM. I assume those tunes worked just fine at some point.
 

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Discussion Starter · #3 ·
Some thoughts I have:

-Did they send out your old injectors for testing and confirm they were bad? (hopefully this is a yes).
-IF previous was a yes....then its possible that the injectors are bad again due to outside influence (assuming the same outside influence that occurred with the original). Debris or something. how many miles on the new injectors?

I really question if its the tune as they suspect honestly, as the tune will not change over time. The sensor inputs could that drive the ecm's math, but the actual tune is a set calibration.

Take that V2 and ensure you save down your current tunes before even thinking about flashing though just in case. EPA has cracked down as you know and getting a tune to support your lack of smog parts is going to be a real task nowadays.

SO if you have ensured you have no harness problems to those cylinders (no chaffed wires or shorts)....its possible its an ECM problem. I just question its change over time, BUT electrical can be very sporadic for no conceivable reason. if you decided to do a new ecm....you could install your tunes onto the new ECM. I assume those tunes worked just fine at some point.
Thanks for the reply! I just heard back from the shop. I misspoke on the tune, but the drivers is still the suspected issue. I didn't originally have the truck tuned, but it has a dsp5 switch which means it should be efi correct? The shop can't figure out a way to pull the tune onto my tune tool and it's been so many years, I don't remember how the process works either. I agree though that the best course is to download the tune and flash onto a new ecm vs the other COA.

Unfortunately, the injectors were not flow tested, so it's possible they never needed to be replaced in the first place.

There aren't many options where I'm at to work on a truck like mine.
 

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Discussion Starter · #4 ·
I'm guessing the tune is probably locked to the ECU? If that's the case I have to somehow find a way to tune it again?
 

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I'm guessing the tune is probably locked to the ECU? If that's the case I have to somehow find a way to tune it again?
You would have to refresh to stock first, then load a new tune from there. Thats whys its recommended to ensure you have your tunes saved FIRST before you take any further steps

Being the current state of worldly affairs, I unfortunately dont even know what direction to begin to steer you with for the rest brother
 

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Discussion Starter · #6 ·
You would have to refresh to stock first, then load a new tune from there. Thats whys its recommended to ensure you have your tunes saved FIRST before you take any further steps

Being the current state of worldly affairs, I unfortunately dont even know what direction to begin to steer you with for the rest brother
Yeah... Unfortunately, the truck was tuned more than 6 years ago. I never thought we would be where we are today with modified diesels.

Does anyone have any suggestions? My truck is undrivable right now. I know these things can't publicly be mentioned, but am aware that there used to be a handful of guru's with EFI on here. My personal email is [email protected] if anyone can point me in the direction of a proper tune.

I've spent entirely too much money trying to fix this problem...
 

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The only "entity" that can load the stock tune would be a GM dealer but then you would lose the DSP5 tunes unless you have the AutoCal with the truck?
 
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