EFI program to Hptuners
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EFI program to Hptuners The car originally was tuned with EFI, I copied the file using HPtuner, Does everything carry over or do we have to start from scratch?
It did start back up. I am able to write to it using HPT.
It did start back up. I am able to write to it using HPT.
As long as it wasn't programmed with a COS Custom Operating System, everything should be OK. If it was programmed with a COS, you shouldn't have been able to read it
Last edited by Pacer Racer; Jan 19, 2020 at 09:01 AM. Reason: Add more info
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In general, HPT end EFI are both just tools for adjusting the parameters and tables that GM's software developers put there in the first place. Kinda like how different companies make similar tools for turning the nuts and bolts that GM put there.
The exceptions are custom operating systems (which can add some new tables/parameters or change the way existing stuff works) and locked tunes (which can prevent reading and writing by other software).
The exceptions are custom operating systems (which can add some new tables/parameters or change the way existing stuff works) and locked tunes (which can prevent reading and writing by other software).
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...or if the tuner locks it. I suppose there could be other things HPT / EFI could do if they wanted to limit interoperability, but I have yet to hear of anything other than custom OSes and locked tunes.
I had my C5 tuned by a pro while I was in the middle of working on open-source software to read and write the PCM, and the open-source stuff still works too. The process is basically the same no matter who makes the tools that do it - GM, HPT, EFI, or a handful of guys with too much time on their hands.
I had my C5 tuned by a pro while I was in the middle of working on open-source software to read and write the PCM, and the open-source stuff still works too. The process is basically the same no matter who makes the tools that do it - GM, HPT, EFI, or a handful of guys with too much time on their hands.
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That brings up a good point though - I should have mentioned that I only really know about the P01 PCMs for sure. But the P59s are almost identical (our software needed only tiny changes to reflash those), so I'm pretty sure everything I know applies to them too.
Other PCMs, I don't know much. I suspect that reflashing works pretty much the same, and so all of these issues are the same as well... I just don't know for sure.
Other PCMs, I don't know much. I suspect that reflashing works pretty much the same, and so all of these issues are the same as well... I just don't know for sure.
