I'm thinking about doing a trial of a big name 3rd party ECU software for my car to see what potential my car has. It's my understanding after this 6 hour trial of their code that the ECU will return to stock but it's not really stock, it's just their version of stock and not what my ECU was before the trial code was flashed to my ECU.

So my question is: I've heard that some 3rd party ECU tuners might try and protect their code by disabling read function (among other things) on the ECU. I don't know if this particular 3rd party is one of them but if I use the NefMoto Software to backup my ECU before getting the their trial code installed, will I be able to reflash my ECU with my backup even if the 3rd party code disabled read access to the ECU thus removing all signs of the 3rd party code and returning my car to it's true stock state?

I'm think the answer is yes since they didn't disable write access to the ECU and since I don't care to backup the ECU with the trial code on it, having read access disabled shouldn't prevent me from reflashing my ECU with my stock backup but I still wanted to confirm this with you guys.

I'm pretty sure I've successfully created the backup of my ECU. I read / download the bin twice and both files have a matching MD5, ME7Check confirms the CRC of the bin files are valid and it lists my models VAG part #, engine id, etc.. So that should be ready to go.

I would try flashing a Tuned ECU file from here but I didn't see one for my specific car in the forums. I may request one but I'm still learning and the above question is what I'm currently curious about right now.

Car information if needed:
2002 Audi C5/A6 MT6 2.7T

I have a: HEX-USB+CAN cable

Thanks for your time!

Some tunners mess with eeprom, so if you don´t full write the original file you can get some DTC (revo is famous for making things like this)

You have to write Eeprom (where adaptation is saved) and Flash to be back to 100% OEM factory behavior.

"Full" vs "Fast" read doesn't do what you think it does.

Both result in the entire ECU flash image (not eeprom). "Fast" read just uses a local file as a reference, and only downloads the differences (based on checksums).