Diagnosis & Repair
- Check for spark at misfiring cylinder. See IGNITION CHECKS in BASIC TESTING
article. If spark is present, go to next step. If spark is not present, go to step 4).
- Check for open or short in IGF circuit between ECM and ignitor. Ignitor is located near left side of engine. See appropriate wiring diagram in WIRING DIAGRAMS
article. Repair wiring as necessary. If circuit is okay, go to next step.
- Disconnect ignitor 5-pin connector. Access ECM under driver's seat. Turn ignition on. Measure voltage between ground and terminal No. 17 (Blue/Red wire) at ECM E8 connector. See Figure. If voltage is 4.5-5.5 volts, replace ignitor. If voltage is not 4.5-5.5 volts, replace ECM and retest.
- Check for open or short in IGT circuit between ECM and ignitor. See appropriate wiring diagram in WIRING DIAGRAMS
article. Repair wiring as necessary. If circuit is okay, go to next step.
- Access ECM under driver's seat. Backprobing ECM connector, measure voltage between ground and terminal No. 23 (Blue/Black wire) at ECM E8 connector while cranking engine. If voltage is .1-4.5 volts, go to next step. If voltage is not .1-4.5 volts, replace ECM and retest.
- Disconnect ignitor 5-pin connector. Backprobing ECM connector, measure voltage between ground and terminal No. 23 (Blue/Black wire) at ECM E8 connector while cranking engine. If voltage is .1-4.5 volts, go to next step. If voltage is not .1-4.5 volts, replace ECM and retest.
- Turn ignition on. Measure voltage between ground and terminal No. 3 (Black/Red wire) at ignitor wiring harness connector. See Fig 1. If voltage is 9-14 volts, go to next step. If voltage is not 9-14 volts, check and repair ignitor power source circuit. See appropriate wiring diagram in WIRING DIAGRAMS
article.
- Check for an open or short in wiring harness between ignition switch and ignition coil, and between ignition coil and ignitor. See appropriate wiring diagram in WIRING DIAGRAMS
article. Repair wiring as necessary. If wiring harness is okay, go to next step.
- Check ignition coil. See IGNITION CHECKS in BASIC TESTING
article. Replace coil as necessary. If coil is okay, replace ignitor.
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