As far as I know, no mustang ECU supports flex fuel. Never seen one.
I wish it did. Flex fuel rocks.
I am running the Lund version of the Flex fuel tune. Ford uses the front O2's to read ethanol content. HP tuners cracked the ECM for existing Flex fuel vehicles and found that most 2011+ mustangs had the programming, but locked. The thing to realize is the Flex Fuel tune will NOT give the same gains as a dedicated E85 tune but it does give a good measure of protection against detonation and more spark advance. Its more of a convenience since I don't have to check the ethanol content when filling up. If your are looking for max performance, get a dedicated tune.
I am running the Lund version of the Flex fuel tune. Ford uses the front O2's to read ethanol content. HP tuners cracked the ECM for existing Flex fuel vehicles and found that most 2011+ mustangs had the programming, but locked. The thing to realize is the Flex Fuel tune will NOT give the same gains as a dedicated E85 tune but it does give a good measure of protection against detonation and more spark advance. Its more of a convenience since I don't have to check the ethanol content when filling up. If your are looking for max performance, get a dedicated tune.
I will disagree with AED. Flex Fuel tune does not work on my car and my tuner has said it doesnt work on ALL 2011+
I am Lund tuned. He said it will work on most cars but there are some that it doesnt work on. I am on a dedicated E85 tune now.