Do not touch or disconnect any
cables from the coils while the
engine is running or being
cranked by the starter.
The ignition system produces
high voltages that can be fatal.
Avoid contact with exposed
terminals. Use extreme caution
when working on a car with the
ignition switched on or the
engine running.
Connect and disconnect the
DME system wiring and test
equipment leads only when the
ignition is OFF.
Before operating the starter
without starting the engine (for
example when making a
compression test) always
disable the ignition.
Knock sensors (
arrows
) monitor the
combustion chamber for engine-
damaging knock. Two sensors monitor
three cylinders each. If engine knock is
detected, the ignition point is retarded
by the ECM.
Note:
When knock is detected, ignition timing
will be retarded at the selective
cylinder(s) by 3° increments. If knock is
no longer detected, the timing will be
advanced in 1° increments.
Ignition timing is electronically mapped
and not adjustable. The ECM uses
engine load, engine speed, coolant
temperature, knock detection and
intake air temperature as the basic
inputs for timing control. A three
Ignition System
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