car ECU programing help please

Hi Aaron,

First of all, this forum is intended for people who have questions on Microsoft software and specifically here for people who use Microsoft Office 365 and other MS Azure solutions. I think you will get better anwers on your questions in other fora and for that I would like to direct you to IOT or specific brand forums that are to be found on the internet.
As already suggested, notepad++ can do the job to compare two files, as well as Microsoft Visual Studio Code that is capable of building and comparing multiple type of files and scripts. Testing such a program should probably done with specific emulators and I would like to point you to other places on the internet to do so.