Quote Originally Posted by delcowizzid View Post
When you are flashing it do you have a separate switched ignition to the ecu so it has both solid 12v and switched 12v because you need to key off the ignition power while retaining the constant 12v feeds for the tune to stay flashed or it will revert to the old vin number and old vats on tune

Oh... no... I don't have that! I'm using a bench harness, I had no idea that was a requirement! That explains the VIN number resetting itself. However, when I read back the program and check it in TunerCATs, it still has the same settings I chose for VATS so it *seems* like that setting is being saved properly. I will definitely modify my harness now though. How long does it need constant power to stay on after switching off ignition power?