Conditions for Running the DTC

WARNING: This page is about a different car, the 2008 GMC Yukon and 2008 Chevrolet Tahoe. However, it is still accessible from the selected car via links, so may be relevant.

DTC P0340, P0341, P0641, or P0651 is not set.
The engine is cranking or running.
The mass air flow (MAF) is greater than 3 grams per second.
The DTC runs continuously when the above conditions are met.