Section 12 (Engine Control System - Basic Engine Testing): Introduction
WARNING: This page is about a different car, the 1998 Pontiac Trans Sport, 1998 Oldsmobile Silhouette, and 1998 Chevrolet Venture. However, it is still accessible from the selected car via links, so may be relevant.
The following diagnostic steps help prevent overlooking simple problems. This is also where to begin diagnosis for no-start condition.
The first step in diagnosing any driveability problem is verifying the customer's complaint by test driving vehicle under the conditions during which the problem reportedly occurred.
Before entering self-diagnostics, perform a careful and complete visual inspection. Most engine control problems result from mechanical breakdowns, poor electrical connections or damaged/misrouted vacuum hoses. Before condemning the computerized system, perform each test listed in this article.
NOTE:
Unless otherwise instructed in test procedures, perform all voltage tests using a Digital Volt-Ohmmeter (DVOM) with a minimum 10-megohm input impedance.