FREE REPAIR MANUALS & LABOR GUIDES 1982-2013 Vehicles
Courtesy of Operation CHARM: Car repair manuals for everyone.

Spark Plug: Testing and Inspection

INSPECTION OF SPARK PLUGS

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





1. REMOVE IGNITION COILS ASSEMBLIES.
2. INSPECT ELECTRODE.



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

Standard correct insulation resistance: 10 M-Ohms or more

^ If the resistance is less than specified, proceed to step 3.

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

(SIMPLE METHOD)
(a) Quickly race the engine to 4.000 rpm 5 times.
(b) Remove the spark plug. (See step 6)



(c) Visually check the spark plug.
^ If the electrode is dry..... OK
^ If the electrode is wet..... Proceed to step 4
(d) Reinstall the spark plug. (See step 7)

3. REMOVE SPARK PLUGS.



- Using a 16 mm plug wrench, remove the 6 spark plugs.
4. VISUALLY INSPECT SPARK PLUGS.



- Check the spark plug for thread damage and insulator damage.
^ If abnormal, replace the spark plug.

Recommended spark plug:
PK20R11 for ND
BKR6EP11 for NGK





5. 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.)

NOTE: 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.

6. CLEAN SPARK PLUGS.



- If the electrode has traces of wet carbon, allow it to dry and then clean with a spark plug cleaner.
- If there are traces of oil, remove it with gasoline before using the spark plug cleaner.

Air pressure: Below 588 kPa (85 psi)
Duration: 20 seconds or less


7. REINSTALL SPARK PLUGS.



- Using a 16 mm plug wrench, install the 6 spark plugs.

Torque: 18 Nm (13 ft.lb)

8. REINSTALL IGNITION COILS ASSEMBLIES.