DTC will set when the following conditions are present:

WARNING: This page is about a different car, the 1997 GMC Savana, 1997 Chevrolet Chevy Van, and 1997 Chevrolet Chevy Express. However, it is still accessible from the selected car via links, so may be relevant.

DTC P0327 is not set.
Engine has been running for at least 120 seconds.
System voltage is greater than 10 volts but less than 17.1 volts.
VCM detects a problem with KS module circuitry that causes a continuous knock condition.
Conditions are present for up to .5 second.