Spark Check
- Perform self diagnostic QUICK TEST to check for ignition-related fault codes, and repair as necessary. See QUICK TEST in the TESTS W/CODES article. If no fault codes are retrieved, check ignition system wiring harness connectors for corrosion and tight fit. See the WIRING DIAGRAMS article. Clean or repair connectors as necessary.
- If wiring and connectors are okay, use Neon Bulb Spark Tester (D89P-6666-A) to check for spark at each spark plug wire while cranking engine. If spark is strong and consistent at each spark plug (one spark per crankshaft revolution), ignition system is okay. If spark is not present, see test procedures under IGNITION SYSTEMS in the TESTS W/CODES article.