These parameters relate to the Electronic Spark Control (knock retard) function available on most Bank-to-Bank systems.  This function is not offered in sequential systems.  Use of the ESC function requires the installation of a GM ESC module and knock sensor such as that used on a 1987 Buick Grand National.

Solid valvetrain components, open exhaust systems and many other high-performance engine components inherently create noise that a knock sensor can perceive to be spark knock, even if the engine is running properly.   The end result is that power output can be unnecessarily reduced.

The following parameters can be accessed from the pulldown menus by selecting VIEW/SPARK FUNCTIONS/ESC PARAMETERS:

Max. ESC Retard 
This is the maximum amount of timing retard allowed if the knock sensor is activated.  Even if knock is still detected once this limit is reached, no more timing will be pulled out.

ESC Attack Rate 
This parameter defines the number of degrees to retard the timing every .1 second when the knock sensor is activated.  In other words, this parameter is used to set how fast the timing will be pulled out when knock is detected.  In the above form, with the attack rate set at 5, the timing would be lowered 5 degrees every .1 second until the knock sensor deactivated, or until the maximum ESC retard limit was reached.

ESC Decay Rate
This parameter defines the number of degrees to remove the timing retard every .1 second after the knock sensor becomes inactive.  In other words, after timing is pulled out due to knock detection, this parameter is used to set how fast the timing will be added back in.  If the decay rate is set to 0.50 as above, the timing will come back in at .5 degree per .1 second (or 5 degrees per second) until the ESC retard has reached zero.