Conditions for Setting the DTC: P0326

WARNING: This page is about a different car, the 2010 GMC Sierra and 2010 Chevrolet Silverado. However, it is still accessible from the selected car via links, so may be relevant.

The KS signal indicates an engine knock is present.
The ECM has commanded the spark retard to a value which is more than the calibrated valve, for a specific engine load and speed.
The above conditions exist for more than 5 seconds.