2. Inspect Spark Plugs

NOTE:

Never use a wire brush for cleaning.
Never attempt to adjust the electrode gap on used spark plug.

Remove the ignition coils. See IGNITION COIL .
Check the electrode.
- Using a megger (insulation resistance meter), measure the insulation resistance.
Correct insulation resistance: 10 M/Ohms or more

If the resistance is less than the specified value, proceed to step d).

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

Fig 1: Using Tester To Check Spark Plug Insulation Resistance
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
- Simple Method:
  - Quickly race the engine to 4,000 RPM 5 times.
  - Remove the spark plug (See step c).
  - Visually check the spark plug.
    
    Fig 2: Checking Spark Plug Electrode
    Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    
    If the electrode is dry ... OK.
    
    If the electrode is wet... Proceed to step d).
  - Reinstall the spark plug. See step g).
Using a 16 mm plug wrench, remove the spark plugs.

Fig 3: Removing Spark Plug
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
Check the spark plug for thread damage and insulator damage.
If abnormal, replace the spark plug.

Fig 4: Recommended Replacement Spark Plugs
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
Check the spark plug electrode gap.

Fig 5: Checking Spark Plug Gap
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Maximum electrode gap for used spark plug:
1. 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. 1.0 - 1.1 mm (0.039 - 0.043 in.)
NOTE: When 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 a used plug.
Clean the spark plugs.

Fig 6: Cleaning Spark Plug
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

If the electrode has traces of wet carbon, make it dry and then clean it with a spark plug cleaner.

Air pressure: Below 588 kPa (6 kgf/cm ² , 85 psi)

Duration: 20 seconds or less

NOTE: If there are traces of oil, remove them with gasoline before using the spark plug cleaner.
Using a 16 mm plug wrench, install the spark plugs.
Torque: 25 N.m (255 kgf.cm, 19 ft.lbf)
Reinstall the ignition coils. See IGNITION COIL .