Section 233 (Engine Controls - Self-Diagnostics): Summary
WARNING: This page is about a different car, the 2003 Pontiac Montana, 2003 Oldsmobile Silhouette, and 2003 Chevrolet Venture. However, it is still accessible from the selected car via links, so may be relevant.
If no hard fault DTCs are present, driveability symptoms exist or intermittent DTC(s) exist, proceed to SYMPTOMS in TROUBLE SHOOTING - NO CODES - 3.4L MONTANA, SILHOUETTE & VENTURE article for diagnosis by symptom (i.e., ROUGH IDLE, NO-START, etc.) or intermittent diagnostic procedures.