Diagnostic Aids

WARNING: This page is about a different car, the 2001 GMC Savana, 2001 Chevrolet RV Cutaway, 2001 Chevrolet Cutaway, and 2001 Chevrolet Chevy Express. However, it is still accessible from the selected car via links, so may be relevant.

Fuel contamination, such as water and alcohol will effect fuel trim.
A malfunctioning Mass Airflow (MAF) sensor can cause a rich condition and set this DTC. See DTC P0101: MAF SENSOR PERFORMANCE .
Using scan tool, review failure records.