Spark Plug: Testing and Inspection

NOTICE:
- Never use a wire brush for cleaning.
- Never attempt to adjust the electrode gap on a used spark plug.
- Spark plugs should be replaced every 100,000 km (60,000 miles).




1. INSPECT ELECTRODE
- Using a megger (insulation resistance meter), measure the insulation resistance.

Standard correct Insulation resistance: 10 M ohm or more

- If the resistance is less than specified, proceed to step 4.

HINT: If a megger is not available, the following simple method of inspection provides fairly accurate results.

Simple Method:
- Quickly race the engine to 4,000 rpm 5 times.
- Remove the spark plug. (See step 2)

- Visually check the spark plug.
- If the electrode is dry ... OK
- If the electrode is wet ... Proceed to step 3
- Reinstall the spark plug. (See step 6)
2. REMOVE SPARK PLUGS
- Using a 16 mm plug wrench, remove the 4 spark plugs.
3. VISUALLY INSPECT SPARK PLUGS
- Check the spark plug for thread damage and insulator damage.
- If abnormal, replace the spark plug.

Recommended spark plug:
ND: PK20R11
NGK: BKR6EP-11




4. INSPECT ELECTRODE GAP

Maximum electrode gap for used spark plug:
1.3 mm (0.051 In.)

- If the gap is greater than maximum, replace the spark plug.

Correct electrode gap for new spark plug:
1.1 mm (0.043 in.)

NOTICE: If adjusting the gap of a new spark plug, bend only the base of the ground electrode. Do not touch the tip. Never attempt to adjust the gap on the used plug.