Operation CHARM: Car repair manuals for everyone.
Manuals through 2025 now available!

Our trusted friends have launched a new website named LEMON, which has newer manuals. It also contains all the CHARM manuals.

LEMON is the spiritual successor to CHARM, I recommend you try it!

Link: lemon-manuals.la or lemon-manuals.org.ua

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Spark Plug: Testing and Inspection




INSPECTION
Check the following points. If a problem is found, replace the spark plug.
^ Damaged insulation
^ Worn electrodes
^ Carbon deposits
If cleaning is necessary, use a plug cleaner or a wire brush. Clean the upper insulator, also.
^ Damaged gasket
^ Burnt

Plug gap
Refer to the Vehicle Emission Control Information (VECI) decal, located in the engine compartment for spark plug gap.