Conditions for Setting the DTC: P0300
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.
The ECM detects a crankshaft rotation speed variation indicating a misfire rate sufficient to cause emissions levels to exceed a predetermined value for greater than 1,000 crankshaft revolutions, 200 crankshaft revolutions for catalyst damaging misfire.