Holley COMMANDER 950 - Manual (Page 62)

62
Idle spark control – These parameters allow the ECU to adjust the idle spark timing to control the engine idle speed. This
function can be turned on or off.
The P term: adjusts the timing to assist in idle stabilization.
The D term: compensates for overshoot.
The Max TPS for idle: tells the ECU when to stop trying to adjust the engine timing to control engine speed.
Figure 46
Knock Control – The ECU can optionally be equipped with a GM knock module and a corresponding knock sensor. If so
equipped, when the ECU senses knock, it will retard the timing and then start returning the timing to the original value. The
ECU should not be programmed to some high timing value and then rely on the knock detection feature to adjust the timing.
This will surely result in engine destruction. Instead, the timing map should be adjusted as correctly as possible and the knock
sensor used to compensate for the occasional anomaly.
Retard Rate – This is the amount the ECU will retard the timing when a knock is detected.
Maximum Retard – This is the maximum amount timing will be retarded if a continuous knock is detected.
Restore Rate – This is the amount of time the ECU waits between incremental steps to restore the timing back to the desired
value. The step size is one degree of timing.
Factory knock modules are not compatible with high-performance engines with solid lifter camshafts, some aftermarket
pistons, and some types of exhaust systems, due to the noise that they produce. For these applications, the use of a special
knock control device may be employed.
Figure 47