Engine Controls - Tests W/Codes - EEC-IV (4.0L): Introduction

Perform all steps in BASIC TESTING - 4.0L article in the ENGINE PERFORMANCE section. If no fault is found while performing steps in BASIC TESTING , proceed with self-diagnostics. If no diagnostic trouble codes or only pass codes (system functioning properly) are found during self-diagnostics, proceed to appropriate TESTS W/O CODES (EEC-IV) article in the ENGINE PERFORMANCE section below for diagnosis by symptom.

• TESTS W/O CODES - EEC-IV (for Aerostar)
• TESTS W/O CODES - EEC-IV (for Explorer)