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DIGITAL ENGINE CONTROL SYSTEM 7
Figure 7.15
Fast Correction
Spark Advance
FPO
one degree of spark advance to cause knocking, more than one degree must be
removed to eliminate knocking). The fast correction scheme is depicted in
Figure 7.15.
In the slow correction scheme (Figure 7.16), spark advance is decreased by
one (or more) degree each time knock is detected, until no knocking is
detected. The spark advance proceeds in one-degree increments after many
engine cycles.
Figure 7.16
Slow Correction
Spark Advance
FPO
UNDERSTANDING AUTOMOTIVE ELECTRONICS 249