Diagnostic Aids

WARNING: This page is about a different car, the 2020 Buick Regal and 2019 Buick Regal. However, it is still accessible from the selected car via links, so may be relevant.

This DTC has a higher priority over any misfire DTC. Diagnose the fuel system, not the ignition system.
A restricted fuel injector may set the DTC.
A high resistance condition on the component circuits may cause the DTC to set.
A drop in system voltage during a cold start may set this DTC.