An injector sleeve secures the fuel injector, seals it to prevent leaks, and dampens vibrations. Made of durable materials like stainless steel, the sleeve ensures the injector is properly positioned to deliver fuel efficiently into the combustion chamber. Proper installation and maintenance of the injector sleeve is crucial for optimal engine performance, fuel economy, and emissions control. Problems with the sleeve can lead to issues like misfiring, rough idling, and decreased power. The injector sleeve plays a vital role in the precise functioning of the fuel injection system.