Action Taken When the DTC Sets

WARNING: This page is about a different car, the 2009 Saturn Vue. However, it is still accessible from the selected car via links, so may be relevant.

DTCs P0300-P0306 are Type B DTCs.
When the MIL is flashing, the injector may be disabled for the misfiring cylinder to protect the catalytic converter.
Depending on the conditions that set the code, the engine may go into Open Loop.