Have you ever heard of putting denatured alcohol in with fuel car?

No, it's not advisable to put denatured alcohol in a fuel car. Denatured alcohol is a type of alcohol that has been made unfit for human consumption by adding chemicals like methanol, acetone, or pyridine. These chemicals can damage your car's engine if used as a fuel. Additionally, denatured alcohol has a lower energy density than gasoline, so it will not provide the same performance or fuel economy.