Engines with over 100,000 kilometers can suffer from extensive carbon deposits and excess friction. Gumout Regane High Mileage Fuel System Cleaner reduces friction in the upper cylinder to improve fuel economy, while using P.E.A. (polyetheramine) to effectively remove deposits that other products can’t. Gumout Regane High Mileage Fuel System Cleaner cleans the entire fuel system for maximized performance and fuel economy.