DTC P0300: Notes

• PCM monitors CKP sensor input signal interval time. PCM calculates the change of the interval time for each cylinder. If the change of interval time exceeds the preprogrammed criteria, PCM detects a misfire in the corresponding cylinder. While the engine is running, PCM counts the number of misfires that occurred at 200 crankshaft revolutions and 1,000 crankshaft revolutions  and calculates misfire ratio for each crankshaft revolution. If the ratio exceeds the preprogrammed criteria, PCM determines that a misfire, which can damage the catalytic converter or affect emission performance, has occurred.

Diagnostic support note 

• This is a continuous monitor (MISFIRE).
• The MIL illuminates if the PCM detects the above malfunction condition in two consecutive drive cycles or in one drive cycle while the DTC for the same malfunction has been stored in the PCM.
• The MIL flashes if the PCM detects misfire which can damage the catalytic converter during first drive cycle.
• PENDING CODE is available if the PCM detects the above malfunction condition during the first drive cycle.
• FREEZE FRAME DATA is available.
• DTC is stored in the PCM memory.

• CKP sensor malfunction
• CMP sensor malfunction
• Ignition coil malfunction
• Ignition system malfunction
• Mass airflow sensor contamination
• Excess air suction in intake air system (between mass air flow sensor and dynamic chamber)
• Fuel pump malfunction
• Fuel pressure regulator malfunction
• Fuel line clogged
• Fuel filter clogged
• Fuel leakage in fuel line
• Fuel runout
• Poor quality fuel
• Purge control solenoid valve malfunction
• PCV valve malfunction
• EGR valve malfunction
• Vacuum hose damage or improper connection
• Related connector and terminal malfunction
• Related wiring harness malfunction
• Insufficient compression