Valvoline MaxLife Fuel System Cleaner is specially formulated for high mileage vehicles to remove stubborn deposits, improving fuel economy and performance. This multipurpose cleaner contains detergents designed to attack deposits in the fuel system, which cause hesitation, stumbling, knocking, pinging, higher emissions and erratic gauge readings. Plus, Valvoline MaxLife Fuel System Cleaner removes water from fuel, preventing rust, corrosion and line freeze.