Engine Controls - System/Component Tests - 5.8L EEC-IV: Introduction

NOTE: This article covers 5.8L with Federal emissions and Gross Vehicle Weight (GVW) over 8500 lbs. System and component testing for all other van models is integrated into self-diagnostics procedures. See TESTS W/CODES - 5.8L EEC-V article for testing procedures.

Before testing separate components or systems, perform BASIC DIAGNOSTIC PROCEDURES in the BASIC TESTING - 5.8L article. Since many computer-controlled and monitored components set a trouble code if they malfunction, also perform SELF-DIAGNOSTIC TESTS in the TESTS W/CODES - 5.8L EEC-IV article.

NOTE: Testing individual components does not isolate short or open circuits. Perform all voltage tests with a Digital Volt-Ohmmeter (DVOM) with a minimum 10-megohm input impedance, unless stated otherwise in test procedure. Use ohmmeter to isolate shorted or open wiring harness.

NOTE: For wiring diagrams not shown in testing procedures, see WIRING DIAGRAMS - 5.8L article.

NOTE: In following tests, circuit diagrams and illustrations are courtesy of Ford Motor Co.