Diagnostic Aids

WARNING: This page is about a different car, the 2002 Pontiac Grand Am, 2002 Oldsmobile Alero, 2002 Chevrolet Monte Carlo, and 2002 Chevrolet Impala. However, it is still accessible from the selected car via links, so may be relevant.

Fuel contamination such as water and alcohol will effect the fuel trim.
A bad MAF sensor can cause a rich condition and set this DTC. Refer to DTC P0101: MAF SENSOR PERFORMANCE .
Use a scan tool in order to review Failure Records. If an intermittent condition is suspected, refer to INTERMITTENT CONDITIONS under SELF-DIAGNOSTIC SYSTEM.