Gumout's Fuel Injector & Carburetor Cleaner keeps deposits from forming on these crucial parts to maintain performance and fuel economy. Carbon buildup from combustion can clog fuel injectors and carburetors, limiting the amount of fuel that reaches the engine. Oxygen sensor safe and safe for use in turbocharged and supercharged vehicles. Will not void OEM/manufacturer's warranty. Add entire bottle to nearly empty gasoline tank, then fill tank with up to 21 gallons of gasoline. For best results, do not refill tank until near empty. Use every 3,000 miles.