AE typically only comes into play for a very short time. The job of AE is to keep the cylinder charge from going lean until the VE delivery "catches up." Lean AE settings could start the "knock...

Knock is the audible side effect of pressure increasing rapidly while the crank and piston are not in a position to be driven by the force created by combustion.

Ultimately the game is to create...

In order to stop kock the KS system will reduce spark advance when knock is detected then advance spark back to the ECM desired timing while knock is not occurring. If knock occurrs at any time then...

After failing to reduce knock by adding 1oz MEK per gallon to your 87 octane fuel. :-)

There are interesting discussions about how to do this reasonably well with budget tools. I believe there was a great thread on thirdgen.org. When you consider the aftermarket uses the same sensor...