Engine Ignition System (3MZ-FE): Inspection

NOTE: In the following section, the terms "cold" and "hot" refer to the temperature of the coils. "Cold" means approximately -10°C (14°F) to 50°C (122°F). "Hot" means approximately 50°C (122°F) to 100°C(212°F).

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.

Check the electrode.
1. Using an mega ohmmeter, measure the insulation resistance.
  Correct insulation resistance: 10 MΩ or more
If the resistance is less than the specified value, proceed to step d.

HINT:

If the mega ohmmeter is not available, do the following simple inspection instead.

Fig 1: Measuring Insulation Resistance
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
Alternative inspection method:
1. Quickly accelerate the engine to 4,000 rpm 5 times.
2. Remove the spark plug.
3. Visually check the spark plug.
4. If the electrode is dry, the spark plug is functioning. Proceed to step 2.
5. If the electrode is damp, proceed to step c, d and e.
6. Install the spark plug.

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

If there is any damage, replace the spark plug.

Fig 2: Checking Spark Plug

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

RECOMMENDED SPARK PLUG

DENSO made	SK20R11
NGK made	IFR6A11

Check the spark plug electrode gap.
Maximum electrode gap for used spark plug: 1.3 mm (0.051 in.)

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

Correct electrode gap for new spark plug: 1.0 to 1.1 mm (0.039 to 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 a used plug.

Fig 3: Checking Spark Plug Electrode Gap
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
Clean the spark plugs.
If the electrode has traces of wet carbon, clean the electrode with a spark plug cleaner and then dry it.
- Air pressure: 588 kPa (6 kgf/cm² , 85 psi)
- Duration: 20 seconds or less
HINT:

Only use the spark plug cleaner when the electrode is free of oil. If the electrode has traces of oil, use gasoline to clean off the oil before using the spark plug cleaner.

Fig 4: Cleaning Spark Plugs
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

INSPECT VVT SENSOR

Measure the resistance between the terminals.

Standard:

RESISTANCE CHECK

Temperature	Specified Condition
Cold	835 to 1,400 Ω
Hot	1,060 to 1,645 Ω

If the result is not as specified, replace the sensor.

INSPECT CRANKSHAFT POSITION SENSOR

Measure the resistance between the terminals.

Standard:

RESISTANCE CHECK

Temperature	Specified Condition
Cold	1,630 to 2,740 Ω
Hot	2,065 to 3,225 Ω

If the result is not as specified, replace the sensor.