Fail-Safe Mode
WARNING: This page is about a different car, the 2002 Nissan Maxima and 2002 Infiniti I35. However, it is still accessible from the selected car via links, so may be relevant.
ECM enters fail-safe mode when both DTC P0650 and another DTC, which calls for MIL to light up, are detected at the same time. When in fail-safe mode, engine speed will not rise more than 2500 RPM due to fuel cut.