E-85 alcohol content

You’ll need to change the fuel constant in Fast if you’re going to e85 full time.

You can use a GM flex fuel sensor to read the level of alcohol content and Fast has a setting for that as well. Then you can go back and forth.

I’m at work though and can’t give exact instructions. Maybe this will jog someone else’s memory.

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I’m a noob, but I hope this will get you started. In Fast, navigate to view/system config/fuel calculation param. The fuel energy constant should be set to 0.680 for e85.

In the same window, you can check the box for Fuel flex mode when you have a flex sensor installed and it will adjust the fuel energy constant itself.

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me also.

I have been told 1 is gasoline, .680 is for E-85, and not that I need it .641 is for methanol (just alcohol).

What should I look for number wise in the dashboard with FuelEnCon for a good formula of E-85 ?
I’m not using a flex sensor, but mine is actually set 0.617 for e98. So from 0.680 to 1 will be lower than 85%.

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