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

(Some people have issue connecting. LEMON is investigating. For now, use Firefox or change your DNS server)

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Spark Plug: Testing and Inspection

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 sandlast 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 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: 0.7 - 0.8 mm (0.028 - 0.031 inch)

Limit:
0.95mm (0.037 inch) <3.8L Engine>