Not the case on the G8 GT tune. I threw the switch on, started the car with the default stoich with e85 in the tank and the trims went crazy but the commanded AFR didn't move. So I thought it might have something to do with filling up, or the car knowing there's more fuel in it to start the algorithm or process, but this wasn't the case. Re-Filled it up and threw the tune with flex fuel enabled on it, no change either. So I'm guessing I'm missing some cables/calibrations? I'd guess a 09 Gen IV E38 pcm has the capability of doing this?