Reversing an 2018 EU Camaro to Stock OS 12688025

[bereic]

Hi,

I hope someone can help.

My daughter bought some months ago a used 18' Camaro 2SS AT (EU Version).
We noticed that the 3rd Gear wasn't acting as it should. Sometimes the acceleration was fully there and sometimes not between 48-60km/h. It should be throtteled all the times between 48-60km/h.
So I decided to check the calibration and write a new calibration to the car.

After I hooked up HPT and did a read on the ECM... I noticed that the entries are different compared to my 18' Camaro 2SS AT Convertible (as well EU Version).
The car from my daughter has a also a non common OS on it (12686391), where mine and all other 2018 EU Versions I saw have the 12688025.

The dealer refuses to do a full OEM-flash... he wants to change the ECU... for a lot of money.

So how could I get the Stock OS again on her ECU?

Is it ok to use a my OEM Stock file - change the VIN to hers - and do a "Write entire" ?

Attached our files. Mine is stock and hers I don't know... but doesn't look as stock.

Would really appreciate any help.

Thank you

ECM - 111089 - OS12686391.hpt
StockECM_Benny - 171559 - OS12688025.hpt

[blindsquirrel]

Can only be done using the GM programming tools (or equivalent, something that will interface with GM SPS). HP Tuners only reads/writes 6 of the 8 segments in the Gen 4/Gen 5 ECM. HP Tuners is not a replacement for dealer-level reprogramming tools.

[bereic]

Can only be done using the GM programming tools (or equivalent, something that will interface with GM SPS). HP Tuners only reads/writes 6 of the 8 segments in the Gen 4/Gen 5 ECM. HP Tuners is not a replacement for dealer-level reprogramming tools.

Thx for your answer.
Wondering then how others have changed their OS in these Trheads:

https://forum.hptuners.com/showthrea...l=1#post552601

https://forum.hptuners.com/showthrea...l=1#post592820

https://forum.hptuners.com/showthrea...eed-stock-file

Meaning only the main operating system needs to be changed. It looks like the other segments are correct.

[blindsquirrel]

Is it possible to write one car's .hpt file to a different car, using HPT? Sure! It will not throw up any errors, or stop you from doing it. But it will not write all 8 segments in the ECM.

Do lots of people do this, not knowing any better? Sure they do! Do they then end up with weird problems that are impossible to diagnose? Yep! Do they do other dumb stuff, like writing a file to an incompatible Service Number? Yep, they do that too!

If the Main Operating System is different between two files, no segment swaps are allowed. So you can't swap the one that has to already be matched. I understand you want to do this yourself using the tool you already have to save money, but you might as well argue that you should be able to fly by flapping your arms really fast since you don't want to spend money on an airline ticket.

[blindsquirrel]

And, neither file you posted has the current-release operating system that's up on GM TIS at the moment, they have both been replaced by newer versions.

[bereic]

And, neither file you posted has the current-release operating system that's up on GM TIS at the moment, they have both been replaced by newer versions.

Yes i know .. 12711163 should be the new MOS.But the cars have not been updated to this one yet as this release was after the build date.

I bet someone did the same on the car.. as in the past for the European cars to delete the 3rd gear throttling this was the only way to do it.

I understand what you are trying to explain.I just want to revert that to Stock.
The dealer asks nearly $1400 here for the new ECU and programming, which is just ripping off.

[blindsquirrel]

Then buy the tools and the SPS subscription and do it yourself. After you've spent the large amount of money to do this one ECM, revisit your claim that it's just ripping off.