Engine Controls - Tests W/O Codes - Gasoline: Introduction
Before diagnosing symptoms or intermittent faults, perform steps in appropriate ENGINE PERFORMANCE article.
Use this article to diagnose driveability problems existing when a hard Diagnostic Trouble Code (DTC) is not present.
NOTE:
Some driveability problems may have been corrected by manufacturer with a revised computer calibration chip or computer control unit. Check with manufacturer for latest chip or computer application.
Symptom checks can direct technician to malfunctioning component(s) for further diagnosis. A symptom should lead to a specific component test, 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) DTC was present, but no problem was found during self-diagnostic testing.
NOTE:
For specific testing procedures, refer to the SYSTEM/COMPONENT TESTS - GASOLINE
article. For specifications, see the ADJUSTMENTS
or the SPECIFICATIONS
article.