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




INSPECTION

1. Reconnect negative battery cable.
2. Connect spark plug to high-tension lead.
3. Hold spark plug with insulated pliers 0.2 to 0.39 inch (5 - 10 mm) from a ground.

WARNING: Do not touch vehicle body during following instructions.




4. While holding spark plug, have a second person crank engine. Verify that a strong blue spark jumps from spark plug to ground.




5. If there is no spark or the spark is weak, check for, and implement correction:
- Carbon deposits. Clean out or replace plug.
- Oil fouling. Correct oil problem, replace plug.
- Worn or burnt electrode. If present, replace plug.
- Broken or burned ceramic insulator. If present replace plug.
- Damaged spark plug ring. If so, replace ring.
- Improper spark plug gap. Regap if possible, otherwise replace plug.

A6D Gap: 1.0 - 1.1 mm (0.039 - 0.043 in.)