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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Inspection Procedure 20

Knocking

COMMENT
- The cause is the heat range of the spark plug is inappropriate.

TROUBLESHOOTING HINTS (The most likely causes for this case:)
- Incorrect heat range of the spark plug.

DIAGNOSIS

STEP 1. Check the following items.
Check the following items, and repair or replace the defective items.
a. Check the spark plugs.
b. Fuel quality, octane level.
c. Check if the foreign materials (water, kerosene, etc.) got into fuel.
Then confirm that the malfunction symptom is eliminated.