No. You have to have an alternate fuel vehicle (hybrid or electric) to be able to take the credit.
Flex fuel, green, eco friendly. A hybrid vehicle.
NO! As far as I know the Vibe is NOT a Flex Fuel vehicle. If it is Flex Fuel and can burn E85 it will have a label affixed to the vehicle somewhere. Do NOT use E85 in a non Flex Fuel vehicle.
FlexFuel will be written on the vehicle somewhere if that vehicle is Flex Fuel.
The 2010 Chevrolet Tahoe-Hybrid runs on flex-fuel (unleaded/E85).
E85 or gas.
The 2010 Chevrolet Silverado-1500-Hybrid runs on flex-fuel (unleaded/E85).
If the car is a Flex-Fuel vehicle then yes you can use E85. If it is not a Flex-Fuel vehicle you cannot use E85. Using E85 will damage components. As far as I know your 2006 Pontiac G6 is not a Flex-Fuel vehicle. Reads your owner's manual to be sure.
NO
No, you cannot use E85 or above in any engine not designed for that fuel. You will damage the engine if you do.
If it is a flex fuel vehicle you can burn all you want. If not a flex fuel vehicle immediate damage can result. The Ethanol will damage the seals in the fuel system.
If it is a Flex Fuel vehicle, YES. If not, NO.