Section 29 (Engine Controls - Tests W/Codes - 3.8L): Summary
WARNING: This page is about a different car, the 1995 Pontiac Trans Sport, 1995 Oldsmobile Silhouette, and 1995 Chevrolet Lumina APV. However, it is still accessible from the selected car via links, so may be relevant.
If hard fault codes are not present and driveability symptoms or intermittent codes exist, proceed to TESTS W/O CODES - GASOLINE article for diagnosis by symptom (i.e., ROUGH IDLE, NO START, etc.), or intermittent diagnostic procedures.