Why Choose BBI Injectors Cummins for Your Diesel Engine? When a Cummins diesel engine needs dependable fuel delivery, the quality of its injectors matters. Fuel injectors are responsible for delivering precisely metered fuel into the combustion chamber, making them an important part of engine performance, efficiency, and drivability. For owners looking to replace worn injectors or improve their diesel setup, BBI injectors Cummins are a popular option to consider.