GM 12597871 Sequential Multiport Fuel Injector Kit

First, in vehicles made from 2006 onward, release the fuel pressure and disconnect the cable from the battery's negative terminal. First, take off two parts: the intake manifold service cover and the air intake duct from the cleaner housing to throttle body. For the most recent models, take off the clamp holding the cable, then disconnect the fuel injectors and take out the old gaskets for the spacer and the throttle body. Take off the three fasteners connecting the fuel rail to its bracket, one at each end-point. Unplug the electric wires from all eight fuel injector connections and put the harness for those wires aside. Take out the nuts holding the coolant pipes to their front spots on the fuel rail, next to each mounting stud. Put the coolant pipes somewhere safe. First, remove all fuel rail mounting bolts, and then take the fuel rail and fuel injectors attached together out. Just push up the plastic U-retainer to remove the fuel injector from the fuel rail. Take out the old o-rings from each injector before you put in fresh ones when fitting them back. After undoing all bolts, put back the fuel rail and injectors as a whole unit. Once bolted again, turn the engine on and watch for fuel spills.