P2178 or P2180
WARNING: This page is about a different car, the 2009 Pontiac Torrent and 2009 Chevrolet Equinox. However, it is still accessible from the selected car via links, so may be relevant.
The Long Term Fuel Trim Cruise/Accel is less than -22 percent for 4 seconds, or for a cumulative of 30 seconds.