SYS.OK|MANUAL.DB● LIVE
HOMESERVICE MANUALSSUBARU1998FORESTER L, STANDARDREPAIR AND DIAGNOSIS (SINGLE PAGE)ENGINE PERFORMANCESYSTEMENGINE CONTROLS - BASIC TESTINGIGNITION CHECKSIGNITION CONTROL SYSTEM TESTS
1998 Subaru Forester L, Standard

Ignition Control System Tests

1998 Subaru Forester L, StandardSECTION Ignition Control System Tests
NOTE: Ensure battery is fully charged before performing tests.

  1. Check Ignition System For Proper Spark

    Remove spark plug wire cap from each spark plug. Install a known-good spark plug to spark plug wire and position spark plug so it is grounded to engine. Crank engine. If a spark does not occur at each spark plug go to next step. If a spark occurs at each spark plug, see FUEL PUMP CIRCUIT TESTS .

  2. Check Voltage At Ignition Coil Positive Terminal

    Turn ignition off. Disconnect connector from ignition coil. Turn ignition on. Ensure there is at least 10 volts between ignition coil 3-pin harness connector terminal No. 2 and ground. See Figure. If voltage is as specified, go to next step. If voltage is not as specified, repair harness or connectors as necessary. See appropriate wiring diagram in WIRING DIAGRAMS article in this section.

  3. Check Ignition Coil

    Measure primary resistance between ignition coil terminals. See IGNITION COIL RESISTANCE  table under IGNITION CHECKS. If resistance is not as specified, replace coil. If resistance is as specified, go to next step.
  4. Measure secondary resistance. See IGNITION COIL RESISTANCE  table under IGNITION CHECKS. If resistance is not as specified, replace ignition coil.

  5. Check Harness Between Ignitor & Ignition Coil Connector

    Turn ignition off. Disconnect connector from ignitor. Measure resistance between ignition coil connector terminal No. 5 and ignitor connector terminal No. 1 and ignition coil connector terminal No. 6 and ignitor connector terminal No. 3. Resistance should be one ohm maximum. If resistance is not as specified, repair harness or connector as necessary. See appropriate wiring diagram in WIRING DIAGRAMS article in this section.

  6. Check Ignitor Input Signal

    Reconnect ignitor connector. Backprobe connector terminals to check voltage between ignitor connector terminal No. 1 and ground, and between ignitor connector terminal No. 2 and ground. Ensure input signal voltage fluctuates with engine speed while cranking. If no voltage, replace ignitor. If voltage is 10 volts or more, go to next step.

  7. Check Ignitor Ground Circuit

    Turn ignition off. Disconnect ignitor connector. Measure resistance between ignitor connector terminal No. 3 and engine ground. Resistance should be 5 ohms maximum. If resistance is not as specified, repair harness or connector as necessary. See appropriate wiring diagram in WIRING DIAGRAMS article in this section.

  8. Check Harness Between ECM & Ignitor Connector

    Disconnect connector from ECM. Measure resistance of harness between ECM and ignitor. See ECM & IGNITOR HARNESS TERMINAL IDENTIFICATION  table. If resistance is more than one ohm, Repair open in harness between ECM and ignitor connector. See appropriate wiring diagram in WIRING DIAGRAMS article in this section.
    ECM & IGNITOR HARNESS TERMINAL IDENTIFICATION

    ECM Terminal No. Ignitor Terminal No.
    41 1
    40 2
    94 3
  9. Measure resistance of harness connector between ECM connector terminal No. 41 and ground, and between ECM connector terminal No. 40 and ground. Resistance should be one megohm minimum. If resistance is less than specified, repair short to ground in harness between ECM and ignitor. See appropriate wiring diagram in WIRING DIAGRAMS article in this section. If resistance is as specified check for poor contact in ECM connector. If contact is okay, check fuel pump circuit. See FUEL PUMP CIRCUIT TESTS .
RENDER: 1.0x

NO RELATED

Recommended Tools & Savings

Use the Manual With the Right Hardware

Pair factory procedures with proven DIY tools so the instructions are easier to execute.

Affiliate disclosure: We may earn a commission at no extra cost to you.

Shop Manual-Ready ToolsFree Quote CheckQuote Shield Pro

When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • • You smell fuel, burning insulation, or see smoke.
  • • Brakes feel soft, pull hard to one side, or make grinding noises.
  • • The engine overheats, stalls repeatedly, or misfires under load.
  • • You are missing required tools, torque specs, or safe lifting equipment.
  • • You are not confident in the next step or safety outcome.