Gasoline Extreme is a complete fuel system cleaner that improves fuel economy and power of gasoline engines by safely and effectively cleaning the entire fuel system. Cleans fuel system - deeply cleans, lubricates, and protects any gasoline fuel system and engine including valves, pumps, injectors, rings, pistons, and upper cylinders. Increases fuel economy - boosts mpg by up to 7.9 percent after the fuel system is fully cleaned by providing an effective boost in combustion, fuel economy, and engine power. Restores performance - acts as an engine flush to restore engine power while also working to dissolve gum and varnish, and remove combustion chamber deposits. Fixes issues - resolves several symptoms of rough-running engines in one treatment, including poor fuel economy, rough idling, clogged fuel injectors, and loss of engine power.