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Engine Controls - Basic Diagnostic Procedures - 3.1L: Introduction

Before proceeding with basic diagnostic procedures, ensure testing procedure is followed, as some systems which may result in a no-start condition may cause a Diagnostic Trouble Codes (DTC) to be stored in the Powertrain Control Module (PCM). See DIAGNOSTIC SYSTEM CHECK - ENGINE CONTROLS under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - 3.1L CENTURY, GRAND PRIX & MALIBU article.

If no-start condition still exists after checking and repairing all DTCs, perform a careful and complete visual inspection. Many problems result from mechanical breakdowns, poor electrical connections or damaged/misrouted vacuum hoses. See VISUAL INSPECTION  under PRELIMINARY INSPECTION & ADJUSTMENTS. Before condemning the computerized system, perform each test listed in this article.

NOTE: Perform all voltage tests using a Digital Volt-Ohmmeter (DVOM) or Digital Multimeter (DMM) with a minimum 10-megohm input impedance, unless stated otherwise in test procedure.