FreeFuel ECU patch - a flex fuel implementation to Evo ECU
A while back I updated the 8 rom source with the correct addresses for Evo IX, but I didn't have the software to compile it. I'll dig around, maybe I can find the files, but I did post them on here at some point. If someone is willing to compile them, I don't see why it wouldn't work.
It is worth it to be honest.
My car was on E80 and I stopped to put a little pump into to. It dropped to E61, from 42psi down to 34psi and 10* timing.
I am really looking forward to one day the flex fuel on the XI becomes free, or at least a 1 time fee like the Tephra XMod V3 (although I suppose that is a bit difficult to implement).
My car was on E80 and I stopped to put a little pump into to. It dropped to E61, from 42psi down to 34psi and 10* timing.
I am really looking forward to one day the flex fuel on the XI becomes free, or at least a 1 time fee like the Tephra XMod V3 (although I suppose that is a bit difficult to implement).
It is worth it to be honest.
My car was on E80 and I stopped to put a little pump into to. It dropped to E61, from 42psi down to 34psi and 10* timing.
I am really looking forward to one day the flex fuel on the XI becomes free, or at least a 1 time fee like the Tephra XMod V3 (although I suppose that is a bit difficult to implement).
My car was on E80 and I stopped to put a little pump into to. It dropped to E61, from 42psi down to 34psi and 10* timing.
I am really looking forward to one day the flex fuel on the XI becomes free, or at least a 1 time fee like the Tephra XMod V3 (although I suppose that is a bit difficult to implement).

Is there a go-to flex fuel sensor? Not looking for a kit, just the sensor itself. I see the OEM replacements for the common GM sensor are available cheaply, but are they the same quality as genuine OEM GM sensor parts?
I am not sure if AEM are the actual manufacturers?
I thought Continental and GM were the main two.
@kaj I completely agree with you. Once there is no money in it, I believe it will be released to everyone. That is very unfortunate, because honestly flex fuel on the XI and stock ecu is a serious game changer. I never worry about being on the right/wrong map, don't need to make sure my ECA displays E85 or if I have 20% ethanol left in the tank. Specially in this part of the world, where we don't have ethanol available anywhere, we basically buy our own E99 and mix it with gasoline.
I thought Continental and GM were the main two.
@kaj I completely agree with you. Once there is no money in it, I believe it will be released to everyone. That is very unfortunate, because honestly flex fuel on the XI and stock ecu is a serious game changer. I never worry about being on the right/wrong map, don't need to make sure my ECA displays E85 or if I have 20% ethanol left in the tank. Specially in this part of the world, where we don't have ethanol available anywhere, we basically buy our own E99 and mix it with gasoline.
I am not sure if AEM are the actual manufacturers?
I thought Continental and GM were the main two.
@kaj I completely agree with you. Once there is no money in it, I believe it will be released to everyone. That is very unfortunate, because honestly flex fuel on the XI and stock ecu is a serious game changer. I never worry about being on the right/wrong map, don't need to make sure my ECA displays E85 or if I have 20% ethanol left in the tank. Specially in this part of the world, where we don't have ethanol available anywhere, we basically buy our own E99 and mix it with gasoline.
I thought Continental and GM were the main two.
@kaj I completely agree with you. Once there is no money in it, I believe it will be released to everyone. That is very unfortunate, because honestly flex fuel on the XI and stock ecu is a serious game changer. I never worry about being on the right/wrong map, don't need to make sure my ECA displays E85 or if I have 20% ethanol left in the tank. Specially in this part of the world, where we don't have ethanol available anywhere, we basically buy our own E99 and mix it with gasoline.
AEM doesn't make sensors so you are paying for the sticker. Racetronix sells the Continental sensors for cheap and what I run in my GTR.
Racetronix Flex Fuel Sensors.
Racetronix Flex Fuel Sensors.
AEM doesn't make sensors so you are paying for the sticker. Racetronix sells the Continental sensors for cheap and what I run in my GTR.
Racetronix Flex Fuel Sensors.
Racetronix Flex Fuel Sensors.









