OIL OR ASH ENCRUSTED
If one or more spark plugs are oil or oil ash encrusted,
evaluate engine condition for the cause of oil entry
into that particular combustion chamber.
ELECTRODE GAP BRIDGING
Electrode gap bridging may be traced to loose depos-
its in the combustion chamber. These deposits (2)
accumulate on the spark plugs during continuous
stop-and-go driving. When the engine is suddenly sub-
jected to a high torque load, deposits partially liquefy
and bridge the gap between electrodes (3). This short
circuits the electrodes. Spark plugs with electrode gap
bridging (1) should be replaced.
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IGNITION SYSTEM - SERVICE INFORMATION
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