2UZ-FE ENGINE CONTROL: IGNITION SYSTEM: ON-VEHICLE INSPECTION (2008 Sequoia)

Last Modified: 11-29-2007		1.6 G
Service Category: Engine/Hybrid System	Section: Engine Control
Model Year: 2008	Model: Sequoia	Doc ID: RM000000SM601YX
Title: 2UZ-FE ENGINE CONTROL: IGNITION SYSTEM: ON-VEHICLE INSPECTION (2008 Sequoia)

ON-VEHICLE INSPECTION

1. PERFORM SPARK TEST

(a) Check for DTCs.

NOTICE:

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

(b) Check if sparks occur.

(1) Remove the ignition coils and spark plugs .

(2) Install the spark plug to the ignition coil and connect the ignition coil connector.

(3) Disconnect the 8 injector connectors.

(4) Ground the spark plugs.

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

NOTICE:

Be sure to ground the spark plug when checking.
If the ignition coil has been struck or dropped, replace it.
Do not crank the engine for more than 2 seconds.

(1) Check that the wire harness side connector of the ignition coil with igniter is securely connected.

Result

Result	Proceed to
NG	Connect securely
OK	Go to next step

(2) Perform a spark test on each ignition coil with igniter.

1. If there is a cylinder where sparks do not occur, replace its ignition coil with the ignition coil of a cylinder where sparks occur normally.

2. Crank the engine and visually check that sparks occur at the cylinder with the normally operating ignition coil.

Result

Result	Proceed to
OK	Replace ignition coil with igniter
NG	Go to next step

(3) Check power supply to the ignition coil with igniter.

1. Turn the Ignition Switch ON.

2. Check that there is battery voltage at the ignition coil positive (+) terminal.

Result

Result	Proceed to
NG	Check wiring between ignition switch and ignition coil with igniter
OK	Go to next step

(4) Check the VVT sensor .

(5) Check the crankshaft position sensor .

(6) Check the IGT signal circuit .

(d) Connect the 8 injector connectors.

(e) Install the 8 ignition coils and 8 spark plugs .

2. INSPECT SPARK PLUG

NOTICE:

Do not use a wire brush for cleaning.

(a) 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

If the insulation resistance is below the specified range, replace the spark plug.

HINT:

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

(b) 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.

Recommended Spark Plug

Manufacturer	Spark Plug Type
DENSO made	SK20R11
NGK made	IFR6A11

HINT:

Maximum electrode gap for a used spark plug: 1.3 mm (0.0511 in.)

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

Electrode gap for a new spark plug: 1.0 to 1.1 mm (0.0394 to 0.0433 in.)

NOTICE:

Do not adjust the electrode gap of any spark plug, as the ground electrode tip will be damaged.

(d) If the electrode has traces of wet carbon, allow it to dry and then clean with a spark plug cleaner.

Standard air pressure:

588 kPa (6.0 kgf/cm², 85 psi)

Standard 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.