Engine Controls - Basic Testing - 4.0L: Summary

If no faults were found while performing BASIC DIAGNOSTIC PROCEDURES, proceed to TESTS W/CODES - 4.0L 6-CYL article. If no hard codes are found in self-diagnostics, proceed to appropriate TESTS W/O CODES - 4.0L 6-CYL article for diagnosis by symptom (i.e., ROUGH IDLE, NO START, etc.) or intermittent diagnostic procedures.