The BG Fuel Injection System Cleaner, No. 210, removes rock-hard carbon deposits from fuel injectors, intake valves and ports. Fuel systems, especially those in gasoline direct injection (GDI) vehicles, are finely tuned and extremely sensitive to deposits that build up on fuel system components. Accumulated residues can cause hesitation, rough idle, poor gas mileage and performance loss. Installed using the BG VIA Vehicle Injection Apparatus (No. 9290-200), BG Fuel Injection System Cleaner provides effective cleaning of stubborn fuel system deposits, improved injector spray, a balanced fuel/air ratio and restored gas mileage. Although it’s a powerful professional-use product, BG Fuel Injection System Cleaner is not harmful to any fuel system components, according to the company.