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Engine Ignition System: Inspection

INSPECT SPARK PLUG

NOTE:

Do not use a wire brush for cleaning.
Do not attempt to adjust the electrode gap of a used spark plug.
Spark plug should be replaced every 200,000 km (120,000 miles).

Check the electrode.
1. Using an ohmmeter, measure the insulation resistance.
Fig 1: Inspecting Spark Plug Using Ohmmeter
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Correct insulation resistance: 10 MΩ or more

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

HINT:

If the ohmmeter is not available, do the following simple inspection instead.
Simple inspection method:
1. Run the engine to 4,000 RPM 5 times quickly.
2. Remove the spark plug.
3. Visually check the spark plug.
4. If the electrode is dry. OK.
5. If the electrode is wet. Proceed to step (C).
6. Reinstall the spark plug.

Check the spark plug for any damage on its thread and insulator.

If there is damage, replace the spark plug.

Fig 2: Inspecting Spark Plug Electrode

G03062580

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Recommended spark plug:

RECOMMENDED SPARK PLUG

DENSO made	SK20R11
NGK made	IFR6A11

Fig 3: Checking Spark Plug For Any Damage On Its Thread And Insulator

G03062581

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Check the spark plug electrode gap.

Fig 4: Checking Spark Plug Electrode Gap
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

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:

1.0 to 1.1 mm (0.039 to 0.043 in.)
Clean the spark plugs.

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

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

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

Duration: 20 seconds or less

HINT:

If there are traces of oil, remove it with gasoline before using the spark plug cleaner.

INSPECT VVT SENSOR
1. Using an ohmmeter, measure the resistance between the terminals.
  RESISTANCE:
  
  835 to 1,400 Ω at cold
  
  1,060 to 1,645 Ω at hot
NOTE: "Cold" and "Hot" mean the temperature of the coils themselves. "Cold" is from -10°C (14°F) to 50 °C (122 °F) and "Hot" is from 50 °C (122 °F) to 100 °C (212 °F).
INSPECT CRANKSHAFT POSITION SENSOR
1. Using an ohmmeter, measure the resistance between the terminals.
  RESISTANCE:
  
  1,630 to 2,740 Ω at cold
  
  2,065 to 3,225 Ω at hot
NOTE: "Cold" and "Hot" mean the temperature of the coils themselves. "Cold" is from -10°C (14°F) to 50 °C (122 °F) and "Hot" is from 50 °C (122 °F) to 100 °C (212 °F).