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Engine Controls - Tests W/Codes 3.8L: Introduction

Most engine control problems are the result of mechanical breakdowns, poor electrical connections or damaged vacuum hoses. Before considering the computer system as a possible cause of problems, perform checks and inspections covered in the BASIC TESTING - 3.8L article. Failure to do so may result in lost diagnostic time.

If no faults found performing procedures in the BASIC TESTING - 3.8L article, proceed with DIAGNOSTIC PROCEDURE  under SELF-DIAGNOSTIC SYSTEM. If no fault codes are present and driveability problems exist, proceed to the ENGINE CONTROLS - TESTS W/O CODES 3.8L article for diagnosis by symptom (i.e., ROUGH IDLE, NO START, etc.). If only intermittent codes are present, see INTERMITTENTS in the ENGINE CONTROLS - TESTS W/O CODES 3.8L article.

NOTE: To identify circuits, terminals and wire colors referenced in testing procedures, see VINS K & 1 (RIVIERA) wiring diagram in SYSTEM WIRING DIAGRAMS article.