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

SPARK PLUG TEST




1. Remove the spark plug and connect to the ignition coil.




2. Ground the spark plug outer electrode (body), and crank the engine.
Check that there is an electrical discharge between the electrodes at this time.




SPARK PLUG CHECK AND CLEANING

CAUTION:
- Do not attempt to adjust the gap of the iridium plug.
- Cleaning of the iridium plug may result in damage to the iridium tips. Therefore, if carbon deposits must be removed, use a plug cleaner and complete cleaning within 20 seconds to protect the electrode. Do not use a wire brush.

Check the plug gap and replace if the limit is exceeded.
Standard value: 0.7 - 0.8 mm (0.028 - 0.031 inch)
Limit: 1.2 mm (0.047 inch)