GMC fuel injector systems can come in two varieties: throttle Body Injection and Port Injection systems. Both vary according to where the injectors are mounted in the vehicle, as well as the locations of the sensors. The fuel injectors depend on the sensors to supply information to the main computer of the engine about the airflow, vacuum, temperature and exhaust levels. In turn, the computer regulates when the fuel injectors are activated as well as how long they remain open to release fuel into the engine. The Port Injection systems send fuel directly to the individual cylinders, and the sensors are located around the engine compartment. The second kind of systems are Throttle Body systems, which have two injectors mounted in an aluminum housing, which is then mounted to the intake manifold. Often the required sensors are installed in the same aluminum housing as the injectors. You will also hear references to multi-port fuel injection or sequential port fuel injection systems. With multi-ports, there is a fuel injector for each cylinder, usually located close enough to spray directly into the intake valve. The other type, sequential multi-port fuel injection, uses one injector that opens just before the intake valve for its cylinder opens. But whatever kind of GMC fuel injector system you need, you will find one here from a recognized, brand-name manufacturer.