DTC P0301-P0306: Engine Misfire Detected In Cylinder No. 1-6: Description

WARNING: This page is about a different car, the 2002 Oldsmobile Bravada, 2002 GMC Envoy XL, 2002 GMC Envoy, and 2002 Chevrolet TrailBlazer. However, it is still accessible from the selected car via links, so may be relevant.

The Powertrain Control Module (PCM) uses information from the crankshaft position (CKP) sensor and the camshaft position (CMP) sensor in order to determine when an engine misfire is occurring. By monitoring variations in the crankshaft rotation speed for each cylinder, the PCM is able to detect individual misfire events. DTCs P0301 through P0306 correspond to cylinders 1 through 6. If the PCM is able to determine that a specific cylinder is misfiring, the Diagnostic Trouble Code (DTC) for that cylinder will set. If the misfire is random and on multiple cylinders, DTC P0300 will set. A misfire rate that is high enough can cause three-way catalytic converter damage. The Malfunction Indicator Lamp (MIL) will flash ON and OFF when the conditions for catalytic converter damage are present.