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




1. Check the following and replace the spark plugs as necessary.
- Damaged insulation
- Worn electrode
- Carbon deposits
- If cleaning is necessary, use a plug cleaner or a wire brush. Wipe upper insulator.
- Damaged gasket
- Burnt condition
- Plug gap

Plug gap: 1.0 - 1.1 mm {0.040 - 0.043 in}