Ignition System - Evolution Mitsubishi Lancer Evolution VIII

GENERAL DESCRIPTION

This system is provided with two ignition coils (A and B) with built-in ignition power transistors for the number 1 and number 4 cylinders, and number 2 and number 3 cylinders respectively.

Interruption of the current flowing in the primary side of ignition coil A generates a high voltage in the secondary side of ignition coil A.

The high voltage generated is applied to the spark plugs of number 1 and number 4 cylinders to generate sparks. At the time that the sparks are generated at both spark plugs, if one cylinder is at the compression stroke, the other cylinder is at the exhaust stroke, so that ignition of the compressed air/fuel mixture occurs only for the cylinder which is on the compression stroke.

In the same way, when the primary current flowing in ignition coil B is interrupted, the high voltage thus generated is applied to the spark plugs of number 2 and number 3 cylinders.

The engine control module controls the two ignition power transistors to turn them alternately ON and OFF. This causes the primary currents in the ignition coils to be alternately interrupted and allowed to flow to fire the cylinders in the order 1 - 3 - 4 - 2.

The engine control module determines which ignition coil should be controlled by means of the signals from the camshaft position sensor and from the crankshaft position sensor.

It also detects the crankshaft position in order to provide ignition at the most appropriate timing in response to the engine operation conditions.

When the engine is cold or operated at high altitudes, the ignition timing is slightly advanced to provide optimum performance.

Scheme 49

Scheme 50

KNOCK CONTROL SYSTEM CHECK

Check the knock sensor circuit if diagnostic trouble code, No. P0325 is shown.

Refer to DTC P0325: KNOCK SENSOR CIRCUIT .

IGNITION COIL CHECK

Check by the following procedure, and replace the coil if there is a malfunction.

SECONDARY COIL RESISTANCE CHECK

Measure the resistance between the high-voltage terminals of the ignition coil.

Scheme 51

1. Standard value: 8.5 - 11.5 kohms

Scheme 52

Note. An analog-type ohmmeter should be used.

Note. Connect the negative probe of the ohmmeter to terminal No. 1.

Scheme 53

1. Connect and disconnect 1.5 V battery between terminals No. 2 and No. 3, and observe the ohmmeter whether there is continuity or not.
2. If results do not agree with the figure (Scheme 53) below, replace the primary coil and ignition power transistor assembly.

Scheme 54

1. Measure the resistance of the all spark plug leads.
2. Check the cap and coating for cracks.
3. Measure the resistance. Limit: 19kohms
4. If resistance is greater than 19 kohms, replace the cable.

SPARK PLUG CHECK AND CLEANING

Check the plug gap and replace if the limit is exceeded.

Scheme 55

1. Standard value: 0.7-0.8 mm (0.028-0.031 inch)
2. Limit: 1.0 mm (0.039 inch)

CAMSHAFT POSITION SENSOR CHECK

Refer to DTC P0340: CAMSHAFT POSITION SENSOR CIRCUIT .

CRANKSHAFT POSITION SENSOR CHECK

Refer to DTC P0335: CRANKSHAFT POSITION SENSOR CIRCUIT .

MEASUREMENT METHOD

1. Clamp the spark plug cable (Number 1 or 3) with the secondary pickup. NOTE: Because of the two-cylinder simultaneous ignition system, the waves for two cylinders in each group appear during wave observation. However, wave observation is carried out for the cylinder (Number 1 or 3) with the spark plug cable which has been clamped by the secondary pickup. NOTE: Identification of which cylinder wave pattern is displayed can be difficult, but the wave pattern of the cylinder which is clamped by the secondary pickup will be stable, so this can be used as a reference.
2. Clamp the spark plug cable (Number 1 or 3) with the trigger pickup. NOTE: Clamp the same spark plug cable as the one which has been clamped by the secondary pickup.

Scheme 56

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Scheme 60

1. Wave characteristics: Spark line is high and short.
2. Cause of problem: Spark plug gap is too large.

Scheme 61

1. Wave characteristics: Spark line is low and long, and is sloping. Also, the second half of the spark line is distorted. This could be a result of misfiring.
2. Cause of problem: Spark plug gap is too small.

Scheme 62

1. Wave characteristics: Spark line is low and long, and is sloping. However, there is almost no spark line distortion.
2. Cause of problem: Spark plug gap is fouled.

Scheme 63

1. Wave characteristics: Spark line is high and short. Difficult to distinguish between this and abnormal wave pattern example 1.
2. Cause of problem: Spark plug cable is not properly connected. (Causing a dual ignition)

Scheme 64

1. Wave characteristics: No waves in wave damping section
2. Cause of problem: Short in ignition coil.

Scheme 65

Scheme 66

REMOVAL AND INSTALLATION

Scheme 67

<< A >> POWER STEERING OIL PUMP, BRACKET AND OIL RESERVOIR ASSEMBLY REMOVAL

Note. Tie the removed power steering oil pump, bracket and oil reservoir assembly with a rope and set aside where they cannot hinder the removal of the power steering oil pump bracket.

Remove the power steering oil pump, bracket and oil reservoir assembly with the hoses attached from the power steering oil pump bracket.

Scheme 68

Required Special Tool

1. MD998773: Knock sensor wrench

<< A >> KNOCK SENSOR REMOVAL

Use special tool MD998773 to remove the knock sensor.

Scheme 69

>> A << KNOCK SENSOR INSTALLATION

Use special tool MD998773 to install the knock sensor.

Scheme 70

FASTENER TIGHTENING SPECIFICATIONS

Identifying Fastener Tightening Specifications

GENERAL SPECIFICATIONS

Identifying General Specifications (1 Of 2)

Identifying General Specifications (2 Of 2)

Scheme 71

See also:
• DTC P0325: KNOCK SENSOR CIRCUIT