huh? please explain better did you want to turn off auto stop? turn off AFM??
if you're able to do it your self you could swap a normal engine into it but it's going to be a lot of work.... you will also need to swap the A/C components as well.... pretty much you would be better off getting a 4.8L tahoe and swapping the body components to it.. i.e the hood ,bumper, tailgate stuff...
the 4.8 should get about 20-22mpg with the better aero components with a 6 speed
Just disconnect the hood sensor cable (don't cut it)... this will turn off auto stop and disable remote start as well.
the DIC will say hood is open..
the other option a soft mod is using 3rd party myvolt app ( I have not personally confirmed that it worked but someone claimed you can turn off and turn on or keep the engine on, on the tahoe.)
https://play.google.com/store/apps/details?id=com.thunkable.android.myvoltapp.MyVoltHold&gl=US&pli=1
to disable AFM use range AFM disabler