Can custom tune be destroyed by a reset of ecm, or by unplugging battery, or fuse??>>
#1
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Just wondering as this just happened to me. I have a Diablo handheld with an uploaded custom tune. I noticed the car was not running the way it was supposed to, and the idle was not running at the correct rpm, fuel trims were way off, yadda yadda yadda, even the skip shift light came back on even though it used to be disabled.
If the battery was disconnected, or if the fuse for the ecm was pulled, or something to that matter, is it possible for the ecm to revert back to stock tune, or to destroy itself from the custom tune that was uploaded into it??
Please let me know asap!
I'm also wondering if I had someone upload their own custom tune for a short time, and then reverted my ecm back to a junk file....
If the battery was disconnected, or if the fuse for the ecm was pulled, or something to that matter, is it possible for the ecm to revert back to stock tune, or to destroy itself from the custom tune that was uploaded into it??
Please let me know asap!
I'm also wondering if I had someone upload their own custom tune for a short time, and then reverted my ecm back to a junk file....
#3
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yes... so never ever unplug your battery..... and don't let the car sit for more than 3 days w/out starting it.....
j/k
NO.... A FLASHED TUNE CAN NOT BE REMOVED OTHER THAN REFLASHING THE CAR![Happy](https://ls1tech.com/forums/images/smilies/LS1Tech/gr_stretch.gif)
hell... I have a PCM that I custom tuned 1.5 years ago.... it's still got the same tune I put in it
(it's been sitting in my closet)
Now... fuel trims being off... not idling rigth... that's normalsince the PCM has to relearn these things.....
the skip shift light is strange .... if it was turned off /disabled properly in the PCM there's no reason it should come back on
but basically .... wether flashed w/a Predator, HPP3, Crane/Vinci, LS1 Edit, EFI Live, HP Tuners or anything else that's out there...
The PCM flash chip is being overwritten .... if you write "tuneA" to it.... regardless of power loss "tuneA" will still be in the PCM .... some parameters need to be learned that's what usually causes the poor idle after the battery is discon.....
but ... it is NOT possible for the PCM/ECM to revert to stock tuning via loss of voltage....
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NO.... A FLASHED TUNE CAN NOT BE REMOVED OTHER THAN REFLASHING THE CAR
![Happy](https://ls1tech.com/forums/images/smilies/LS1Tech/gr_stretch.gif)
hell... I have a PCM that I custom tuned 1.5 years ago.... it's still got the same tune I put in it
![Happy](https://ls1tech.com/forums/images/smilies/LS1Tech/gr_stretch.gif)
Now... fuel trims being off... not idling rigth... that's normalsince the PCM has to relearn these things.....
the skip shift light is strange .... if it was turned off /disabled properly in the PCM there's no reason it should come back on
but basically .... wether flashed w/a Predator, HPP3, Crane/Vinci, LS1 Edit, EFI Live, HP Tuners or anything else that's out there...
The PCM flash chip is being overwritten .... if you write "tuneA" to it.... regardless of power loss "tuneA" will still be in the PCM .... some parameters need to be learned that's what usually causes the poor idle after the battery is discon.....
but ... it is NOT possible for the PCM/ECM to revert to stock tuning via loss of voltage....
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Awesome, thank guys!!
Ok then, I need to have a little talk then with someone here, b/c something was definately messed with on my pcm. It for certain was not running on the tune I had uploaded into the car. Dead give away was the fact the car was idling around 780-800rpms like stock, vs the 900-920 rpms for the aftermarket tune I had uploaded.
That given the fact, when I uploaded the new tune (after cam install), the car would fire right up and not stall, even without the pcm relearning. The stock tune before this, and even the original GM tune would just immediately stall out and sounded like trash....
Am I wrong??
Ok then, I need to have a little talk then with someone here, b/c something was definately messed with on my pcm. It for certain was not running on the tune I had uploaded into the car. Dead give away was the fact the car was idling around 780-800rpms like stock, vs the 900-920 rpms for the aftermarket tune I had uploaded.
That given the fact, when I uploaded the new tune (after cam install), the car would fire right up and not stall, even without the pcm relearning. The stock tune before this, and even the original GM tune would just immediately stall out and sounded like trash....
Am I wrong??