Ignition System - Electronic Mitsubishi Mirage II

DESCRIPTION

Mitsubishi breakerless ignition consists of an electronic control module (ignitor), ignition coil, pick-up coil and distributor. The control module is mounted inside the distributor with the pick-up coil assembly.

Chrysler Corp. Imports and Mitsubishi models with turbo engine are equipped with Electronically Controlled Injection (ECI) system, which controls fuel injection and ignition timing retard.

OPERATION

Whenever the ignition is on, the primary circuit of the ignition coil is energized. As the distributor shaft rotates, the armature (reluctor) rotates inside the magnetic pick-up coil (stator) assembly.

As the teeth of the armature pass the pegs of the pick-up coil, a signal is sent to the control module (ignitor). The module then breaks the primary circuit in the coil. This causes a high voltage surge in the coil secondary circuit. This high voltage is required to fire the spark plugs.

Wiring Schematic of Mitsubishi Electronic Ignition System With Internal Control Module. Scheme 1

Note. For wiring schematic of Mitsubishi models with Turbo engines and ECI, see the appropriate article in COMPUTERIZED ENGINE CONTROLS section.

RELUCTOR-TO-PICK-UP COIL AIR GAP

Align teeth of reluctor with pegs of pick-up coil and breaker plate assembly. Using a feeler gauge, check for correct air gap. To adjust, loosen set screws and move pick-up coil.

PICK-UP COIL AIR GAP

TESTING

Note. Ensure battery is fully charged and in good condition before making any tests. Check all wiring, ignition switch, coil, spark plug cables and connectors.

HIGH VOLTAGE TEST

Connect a remote starter switch in the starting circuit. Remove coil wire from distributor cap. Turn ignition on and hold coil wire 1/4" from cylinder block. Crank engine. If no spark or only a weak spark results, perform the following tests.

SECONDARY WIRE RESISTANCE TEST

1. Test coil and spark plug cables with an ohmmeter. DO NOT puncture secondary wires when making the resistance check. Connect leads to each end of the cable.
2. Resistance for Mazda and Mitsubishi vehicles should not exceed 16,000 ohms for each 39" (1 m). For Chrysler Corp. vehicles, resistance should not exceed 22,000 ohms per cable.

IGNITION COIL RESISTANCE TEST

1. Turn ignition off. Remove wires from coil primary terminals to isolate it from the rest of the system. Set an ohmmeter to the low scale, and attach the leads to the coil positive and negative terminals. Check primary resistance reading.
2. Set ohmmeter to x1000 scale, and attach leads to the coil positive terminal and secondary tower. Check secondary resistance reading.

IGNITION COIL RESISTANCE SPECIFICATIONS (OHMS)

MAGNETIC PICK-UP COIL RESISTANCE TEST

Turn ignition off. Set ohmmeter to the x100 scale. Attach leads to pick-up coil's distributor connector terminals. (Scheme 2) Compare resistance readings obtained with table. See PICK-UP COIL RESISTANCE table.

Checking Pick-Up Coil Resistance Attach ohmmeter leads to points shown. Scheme 2

PICK-UP COIL RESISTANCE

IGNITION MODULE TEST

Connect the ignitor, light and battery. (Scheme 3) Using a dry cell battery or continuity tester, apply voltage to the signal input terminal of the ignitor unit. Test light should light when voltage is applied, and go out when voltage is removed. If not, ignitor is bad.

Note. This test can only determine when ignitor is bad. Even if ignitor tests good, it could still be defective.

Checking Ignitor With Battery & Test Light Use low-voltage dry cell battery or ohmmeter. Scheme 3

ESC IGNITOR TEST

1. Warm engine to normal operating temperature. Connect a timing light and set to specification. Check centrifugal spark advance and repair if necessary. Set engine to 1000 RPM.
2. Using a hammer, lightly tap injector mixer mounting stud. Check to see if spark retards. If not, go to next step. If so, measure voltage between ignitor terminal number 6 and ground. If there is 1 volt or less, repair or replace pressure sensor and/or shorted wiring harness. If more than 1 volt is present, replace defective ESC ignitor.
3. Disconnect pressure sensor connector. Check to see if spark timing retards. If not, go to next step. If spark retards, check detonation shielding wire for continuity. If okay, detonation sensor or ESC ignitor is defective. If not, repair or replace shielding harness.
4. Using a hammer, lightly tap injector mixer mounting stud. Check to see if spark timing retards. If not, replace the ESC ignitor or detonation sensor. If spark retards, disconnect detonation sensor connector.
5. Check for spark timing retarding 8°. If not, ESC ignitor is defective. If so, ESC ignitor is okay. Reconnect wiring.

Mitsubishi 1.5L, 2.0L & 2.4L Engines

1. Remove distributor cap, rotor and seal. Remove governor assembly. Remove vacuum control unit. Remove IC ignitor. Remove lead wire. Remove signal rotor shaft screw and 2 breaker plate retaining screws. Remove breaker plate assembly. NOTE: DO NOT clean grease off back of IC ignitor. It is necessary for heat transfer.
2. Remove signal rotor shaft from signal rotor. Remove 2 spring retainers and springs with pliers. Remove governor weights. Mark drive gear location on distributor shaft.
3. Place drive gear on a wooden block and remove drive gear roll pin using a pin punch. Remove drive gear and washer. Remove distributor shaft from housing.

Mitsubishi 1.6L & 2.6L Engines

1. Remove distributor cap and rotor. Mark location of governor springs, weights and pins for reassembly in original location. Remove governor springs. Remove snap rings and governor weights. Remove governor plate retaining bolt and governor plate. NOTE: Governor plate locking bolt is very tight and is retained with Loctite. Use either a box wrench or socket wrench to loosen bolt.
2. Remove governor base and signal rotor assembly. Remove 2 ignitor assembly retaining screws. Remove pick-up coil from the frame. Remove vacuum controller. Remove 2 breaker assembly retaining screws and remove breaker assembly from housing. When breaker assembly is removed, ensure it is placed in a clean work area.
3. Remove 2 screws and bearing retainer from housing. Mark location of drive gear on distributor shaft. Place drive gear on a wooden block and remove roll pin using a pin punch. Remove drive gear from shaft. Remove distributor shaft from housing.

Installing Driven Gear on Distributor Shaft Align marks and install new roll pin. Scheme 4

Mitsubishi 1.8L Engine

1. Remove distributor cap and rotor. Remove 2 vacuum controller mounting screws. Remove snap ring and disconnect vacuum controller link from breaker plate pin. Remove vacuum controller. Remove signal rotor shaft tightening screw.
2. Remove 2 breaker plate mounting screws. Remove signal rotor shaft and breaker plate assembly. Gently tap signal rotor to remove it from the signal rotor using a soft hammer. Remove 2 pick-up coil mounting screws and pick-up coil.
3. Remove governor spring retainers and springs using pliers. Remove governor weights. Mark distributor shaft and drive gear for reassembly reference. Place drive gear on a wooden block and remove drive pin using a pin punch. Remove drive gear and washer. Remove distributor shaft from housing.

REASSEMBLY

Reverse removal procedure. Inspect cap and rotor for cracks and deposits on inside surfaces. Ensure no metallic dust or filings adhere to breaker assembly, and it is clean prior to reassembly. Use new distributor drive gear roll pin.

Exploded View of Mitsubishi Distributor Used With 1.5L, 2.0L & 2.4L Engines. Scheme 5

Exploded View of Mitsubishi Distributor Used With 1.6L & 2.6L Engines Note location of governor springs for reassembly. Scheme 6

Exploded View of Mitsubishi Distributor Used With 1.8L Engine Note location of governor springs for reassembly. Scheme 7

See also:
• PICK-UP COIL RESISTANCE