Ignition System On-Vehicle Inspection

Check for DTCs (LandCruiser RM000000VNG00DX.html).

NOTICE:

If any DTC is output, perform troubleshooting procedures for that DTC.

Remove the 4 ignition coil assemblies and 4 spark plugs (LandCruiser RM0000045AB00BX.html).

Install the spark plug to the ignition coil assembly and connect the ignition coil connector.

Disconnect the 4 fuel injector connectors.

Ground the spark plug.

Visually check that sparks occur while the engine is being cranked.

NOTICE:

1. When performing the inspection, be sure to ground the hexagonal portion or the threaded portion of the spark plug.
   
2. Do not crank the engine for more than 2 seconds.
   
3. Be sure to ground the spark plug when checking.
   
4. If an ignition coil assembly is struck or dropped, replace it with a new one.
   
5. If a spark plug is struck or dropped, replace it with a new one.
   

If sparks do not occur normally in 1 or more cylinders, perform the "Ignition Coil and Spark Test" below.

Spark test flowchart.

1. Check that the wire harness side connector of the ignition coil assembly is securely connected.
   

   Result:

   Result	Proceed to
   NG	Connect securely
   OK	Go to next step

2. Perform spark test on each ignition coil assembly.
   

   1. Replace the ignition coil assembly with a normal one.
      
   2. Perform spark test again.
      

      Result:

      Result	Proceed to
      OK	Replace ignition coil assembly
      NG	Go to next step

3. Inspect the spark plug.
   

   1. If there is a cylinder in which ignition does not occur, interchange the spark plug of that cylinder and the spark plug of a cylinder in which ignition properly occurs.
      
   2. Check that sparks occur in the cylinder in which the properly functioning spark plug was installed.
      

   Result:

   Result	Proceed to
   OK	Replace spark plug
   NG	Inspect ignition system (LandCruiser RM000000XH40ZRX.html)

4. Check the camshaft position sensor (LandCruiser RM000000WBZ0SKX.html).
   

5. Check the crankshaft position sensor (LandCruiser RM000000TCW11OX.html).
   

Connect the 4 fuel injector connectors.

Install the 4 ignition coil assemblies and 4 spark plugs (LandCruiser RM0000045A900BX.html).

Clear DTCs (LandCruiser RM000000VNG00DX.html).

Check the electrode.

1. Using a megohmmeter, measure the insulation resistance.
   

   Standard Insulation Resistance:

   Tester Connection	Condition	Specified Condition
   Spark plug (Terminal part) - Body ground	Always	10 MΩ or higher

   Text in Illustration

   *a

   Ground

   HINT:

   If a megohmmeter is not available, perform the following simple inspection.

Alternative inspection method:

1. Quickly accelerate the engine to 4000 rpm 5 times.
   

2. Remove the spark plug.
   

3. Visually check the spark plug.
   If the electrode is dry, the spark plug is functioning properly. If the electrode is damp, proceed to the next step.
   

Check the spark plug for any damage to its thread and insulator.
If there is damage, replace the spark plug. If not, reinstall the spark plug.

Recommended Spark Plug:

Manufacturer	Spark Plug Type
DENSO	FK20HR-A8

Check the spark plug electrode gap.

Maximum electrode gap for used spark plug:

1.1 mm (0.0433 in.)

Electrode gap for new spark plug:

0.7 to 0.8 mm (0.0276 to 0.0315 in.)

NOTICE:

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 of a used plug.

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 (6.0 kgf/cm², 85 psi)

Duration:

20 seconds or less

HINT:

Only use a 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.