Don't ask why. My daughter put E 85 into her 2007 civic coupe. what do we need to do?

 

Just drain it out of the tank and refill with unleaded gas. There might be a drain plug on the bottom of the gas tank, older models all had them. E-85 won't run right but it shouldn't have damaged anything. You don't have to get every drop out of the system because all gas contains a little ethanol now anyway.

 

it would also help to put an octane booster fuel additive into the tank after u drain it.