Spark Check

Perform self diagnostic QUICK TEST to check for ignition-related fault codes, and repair as necessary. See QUICK TEST in TESTS W/CODES article. If no fault codes are retrieved, check ignition system wiring harness connectors for corrosion and tight fit. See appropriate article:
- For 3.0L vehicles, see WIRING DIAGRAMS .
- For 3.8L vehicles, see WIRING DIAGRAMS .
Clean or repair connectors as necessary.
If wiring and connectors are okay, use Neon Bulb Spark Tester (D8IP-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, go to CIRCUIT TEST JD in TESTS W/CODES article.