How to Install Injen Power-Flow Cold Air Intake w/ Heat Shield - Polished on your Sierra

Pull the engine cover off the intake manifold.

Unplug the hard vacuum line connected to the air intake resonator box.

Loosen the throttle body clamp located on the air intake duct (A). Loosen the second clamp that connects the air intake duct to the mass air flow sensor (B).

Once both clamps have been loosened at the throttle body and the mass air flow sensor, continue to remove the plastic air intake duct.

depress clip on the electrical harness connector and remove harness from the mass air flow sensor.

Loosen clamp that connects the mass air flow sensor to the air box cleaner. Remove the mass air flow sensor from the air box cleaner.

Pull the entire air box cleaner for the engine compartment.

Remove the factory crank case line from the vehicle.

Press the urethane step hose over the throttle body until it butts up against the rim. Once you have adjusted the step hose, continue to tighten the power-band located over the throttle body side.

Loosen the 2 bolts holding in the air box tray close to the engine. Save the 2 bolts which will be re-installed for the injen heat shield.

Press the 4” hump hose over the outlet side of the mass air flow sensor. Use two clamps and tighten the clamp on the mass air flow sensor. Note: The sensor is directional. Follow arrow.

Press the 3-3/4” straight hose over the inlet side of the mass air flow sensor. Use two clamps and tighten the clamp on the mass air sensor. Make sure the MAF is going in the correct direction.

Install the adaptor to the heat shield.

Secure the adaptor using provided M6 button head screws, Tighten using 6mm allen key.

Attach the trim seal to the top of the heat shield.

Install the filter to the adaptor and tighten using 8mm nut driver.

Install the heat shield assembly into the vehicle and position the brackets on the heat shield to the m6 inserts on the air box bracket from earlier step.

Secure the heat shield using the factory bolts and tighten using 10mm socket or wrench.

Attach the MAF sensor assembly to the adaptor. Make sure the hump hose is on the adaptor.

Tighten the clamp on the adaptor only using 8mm nut driver.

The electrical sensor harness is now press over the mass air flow sensor.

Lower the cast intake into the engine compartment as shown above. Align the press the lower inlet side into 3 3/4” straight hose.

Prior to inserting the outlet end into the throttle body step hose, install the provided 11” -10mm vacuum line over the intake port.

Continue to press the intake end into the step hose and tighten the power-band using 8mm nut driver.

Once you have aligned the entire intake, continue to tighten all nuts, bolts and clamps. Now, press the engine cover back to its original location.

Start your engine and allow the on board computer to adjust to the added volume or air. Listen to the engine and make sure there are no rattles or spikes when idling. Enjoy the added power and performance of the best intake system today.