7 -
Termination oscillations
Note:
See
Ignition coil assembly, testing
and replacing
as described later.
Table b. Ignition trace diagnostics
Parameter
Ignition
voltage
low
Ignition
voltage
high
Spark plug
electrode
gap
too small
too big
Spark plug
electrode
condition
-
worn/burnt
Spark plug
electrode
temperature
too high
too low
Engine
compression
too low
too high
Spark plug
wire(s)
-
faulty
Fuel air
mixture
-
too lean
Misfire detection
Engine misfire, the result of inefficient
combustion in one or more cylinders,
may be caused by a variety of
malfunctions in various subsystems.
The OBD II system incorporated into
the MS 42.0 and MS 43.0 engine
management systems is designed to
detect and warn of misfire faults during
engine operation. Misfire fault codes
are listed in
Table c. Misfire fault
codes
. For a detailed list of fault codes
see
OBD On Board Diagnostics
.
Ignition System
http://ebahn.bentleypublishers.com/BMW/3/E46/Repair%20Manuals/1...
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Summary of Contents for 1999-2005 M3
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