DTC P0300: Random/Multiple Cylinder Misfire Detected: General Description

The PCM monitors variations in the crankshaft rotational speed to determine if any misfires occurred. When a misfire occurs, the rotational speed of the crankshaft slows down. The PCM then identifies the specific cylinder in which the misfire occurred, and counts individual misfire events. A random misfire (P0300) indicates two or more cylinders are misfiring.

Misfires can be caused by a lack of combustion in a cylinder/s due to: the absence of spark, poor fuel metering, poor compression, or timing. Even a small number of misfires may result in excessive exhaust emissions, due to the unburned fuel. Increased misfire rates can cause damage to the catalytic converter.