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 Check and Cleaning

SPARK PLUG CHECK AND CLEANING

CAUTION





^ Never attempt to adjust the gap of the iridium plug.
^ Do not attempt to clean the spark plug because it may result in damage to the electrode. However, if carbon deposits must be removed, using a sand blast type plug cleaner, complete the cleaning within 20 seconds to protect the electrode. Do not use a wire brush.


NOTE:
Obey the maintenance interval of the relevant vehicle for the spark plug replacement. If the plug gap and insulation resistance are normal, check the plug state and clean it if necessary.

SPARK PLUG GAP CHECK





Check the plug gap with the wire type plug gauge. Replace it if the limit is exceeded.

Standard value: 0.5 - 0.6 mm (0.020 - 0.023 inch)
Limit: 0.75mm (0.029 inch)

SPARK PLUG INSULATION RESISTANCE CHECK





1. Measure the insulation resistance. If the insulation resistance of the spark plug is under the limited value, clean the plug within 20 seconds using a plug cleaner.
2. After cleaning, measure the insulation resistance again. Replace the plug unless it is within the limited value.
Limit: Minimum 10 Mohms