Conditions for Setting the DTC: P0401
WARNING: This page is about a different car, the 2008 Suzuki Swift +, 2008 Pontiac Wave, and 2008 Chevrolet Aveo. However, it is still accessible from the selected car via links, so may be relevant.
The MAP changes monitored by the ECM during the EGR flow tests indicate an insufficient amount of EGR flow.