And everything done with computers these days leave some kind of electronic mark.
I urge caution here guys. They can scan more deeply than we might want to believe. Have read they can tell if the ECM settings were changed, but might not be able to tell exactly what they were. If you were to do it there could
be 2 marks depending on history recorded, one for your power flash and one to reset it to OEM. If it were done by Nissan, there will likely be a record of it. If it wasn't done by Nissan, you might a have a fight on your hands. Is it really worth it to tinker with it while still under warranty? This is a little different than checking transmission fluid levels.
2016 XD 5.0 Cummins Pro4x Pearl White, Build date 4/2016, Conven & Util + Audio, Bumper Step Assist, Dark Chrome Step Rails (needed someplace to clean my boots before entering!), Front & Rear Splash Guards. 2004 Subaru Forester, 99.5 Powerstroke with mods, previously a 2011 Xterra Pro-4X - (a fine vehicle but was upsized by the XD)