How to Replace a Fuel Injector in a Chevy Avalanche

Determine which fuel injector your Chevy Avalanche will need. This depends not only on the make and model, but also the engine size. Models made from 2001 to 2006 may have a 5.3L or 8.1L engine and models made after 2006 can have a 5.3L or 6.0L engine.

Relieve the fuel system pressure. Disconnect the negative battery cable with a socket wrench and remove the bolts from the engine sight shield bracket with a socket wrench. Detach the cables for the accelerator control and cruise control from the cable bracket and throttle body. Remove the retainer nut for the upper engine wire harness and move the upper engine wire harness aside.

Label the fuel injector connectors for future reference and pull the top part of the injector connector up without pulling it past the top of the white portion. Push the tab on the lower side of the connector to release it from the injector.

Detach the fuel send and return lines from the fuel rail with a socket wrench. Remove the fuel pressure regulator vacuum line and the crossover fuel rail retaining screw. Take out the mounting bolts for the fuel rail with a socket wrench so you can remove the fuel rail.

Insert the fork of a fuel injector assembly removal tool between the fuel rail pod and the three retaining clip ledges. Pry the fuel injector out of the fuel rail pod. Discard the O-ring seals and retainer clip.

Install the new fuel injectors by reversing the removal procedure. Lubricate the injector O-ring seals with clean engine oil prior to installation. Apply a 5mm band of threadlock to the fuel rail retaining bolts and use a torque wrench to tighten them to 89 inch pounds. Torque the crossover pipe retaining screw to 34 inch pounds.

Connect the wiring harnesses according to the labels you made earlier. Torque the upper engine wire harness retainer nut to 49 inch pounds and the engine sight shield bolts to 89 inch pounds.