Diesel Data: Automotive Repair

Ignition System: Testing and Inspection

ON-VEHICLE INSPECTION

NOTE: "Cold" and "Hot" in these sentences express 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).


1. INSPECT IGNITION COIL (WITH IGNITER) AND SPARK TEST
Check that the spark occurs.

1. Remove the ignition coils.
2. Remove the spark plugs.
3. Install the spark plugs to each ignition coil, and connect the ignition coil connector.
4. Disconnect the 4 injector connectors.
5. Ground the spark plug.
6. Check if the spark occurs while the engine is being cranked.

NOTE: To prevent gasoline from being injected from injectors during this test, crank the engine for no more than 5 - 10 seconds at time.




If the spark does not occur, do the test as shown.

7. Using a 16 mm plug wrench, reinstall the spark plugs.

Torque: 25 N.m (255 kgf.cm, 19 ft.lbf)

8. Reinstall the ignition coils.

2. INSPECT SPARK PLUGS

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

a. Remove the ignition coils.

b. Check the electrode.




- Using a megger (insulation resistance meter), measure the insulation resistance.

Correct insulation resistance: 10 MOhms or more

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

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




- Simple Method:
- Quickly race the engine to 4,000 rpm 5 times.
- Remove the spark plug (See step (c)).
- Visually check the spark plug.
If the electrode is dry ... OK.
If the electrode is wet ... Proceed to step (d).

- Reinstall the spark plug (See step (g)).




c. Using a 16 mm plug wrench, remove the spark plugs.
d. Check the spark plug for thread damage and insulator damage.




If abnormal, replace the spark plug.




e. 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 maximum, replace the spark plug.

Correct electrode gap for new spark plug:
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.




f. Clean the spark plugs.
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/sq.cm, 85 psi)

Duration: 20 seconds or less

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

g. Using a 16 mm plug wrench, install the spark plugs.

Torque: 25 N.m (255 kgf.cm, 19 ft.lbf)

h. Reinstall the ignition coils.

3. INSPECT CAMSHAFT POSITION SENSOR

a. Remove the sensor.







b. Using an ohmmeter, measure the resistance between the terminals.
If the resistance is not as specified, replace the sensor.

c. Reconnect the sensor connector.

4. INSPECT CRANKSHAFT POSITION SENSOR

a. Remove the front engine under cover.
b. Disconnect the A/C compressor.
c. Disconnect the connector from the oil level gauge clamp.







d. Using an ohmmeter, measure the resistance between the terminals.
If the resistance is not as specified, replace the sensor.

e. Reinstall the connector with the oil level gauge clamp.
f. Reconnect the A/C compressor.
g. Reinstall the front engine under cover.