Engine Controls - Tests W/O Codes: Introduction

Before diagnosing symptoms or intermittent faults, perform steps in BASIC TESTING article and TESTS W/CODES article. Use this article to diagnose driveability problems existing when a hard fault code is not present.

See BASIC TESTING article.
See SELF-DIAGNOSTICS article.

NOTE: Some driveability problems may have been corrected by manufacturer with a revised Powertrain Control Module (PCM). Check with manufacturer for latest PCM application.

Symptom checks can direct the technician to malfunctioning component(s) for further diagnosis. A symptom should lead to a specific component, system test or an adjustment.

Use intermittent test procedures to locate driveability problems that DO NOT occur when vehicle is being tested. These test procedures should also be used if a soft (intermittent) trouble code was present, but no problem was found during self-diagnostic testing. See INTERMITTENT PROBLEM DIAGNOSIS under INTERMITTENTS.

NOTE: For specific testing procedures, see SYSTEM/COMPONENT TESTS article. For specifications, see ADJUSTMENTS - 4.0L 6-CYL article or SPECIFICATIONS - 4.0L 6-CYL article.