I am in the process of getting a '21 Trackhawk set up for flex fuel. I have applied the patch and completed a write entire. I adjusted all of the parameters needed to enable flex fuel however I can not seem to get it to work. The scanner shows that learning is active and shows 10% alcohol content. I have put over 30 miles on it but content never changes. (Has 10 gallons of e85 in the tank). I just wanted to see if anyone has successfully applied the patch to a '21.