Yukon XL 4WD V8-5.3L (2011)
1. Inspect the spark plug gap. Adjust the gap as needed. Refer to Ignition System Specifications See: Application and ID.
2. Hand start the spark plug in the corresponding cylinder.
Caution: Refer to Fastener Caution See: Service Precautions/Vehicle Damage Warnings/Fastener Caution.
3. Tighten the spark plug to 15 Nm (11 lb ft).
4. Install the spark plug wire to the spark plug.
5. Inspect the spark plug wire for proper installation:
1. Push sideways on each boot in order to inspect the seating.
2. Reinstall any loose boot.
