DTC P0301, P0302, P0303, P0304: Notes

DTC P0301, P0302, P0303, P0304 DETECTION CONDITION AND POSSIBLE CAUSES

DTC P0301 DTC P0302 DTC P0303 DTC P0304	Cylinder No. 1 misfire detected Cylinder No. 2 misfire detected Cylinder No. 3 misfire detected Cylinder No. 4 misfire detected
DETECTION CONDITION	The PCM monitors CKP sensor input signal interval time. The PCM calculates the change of interval time for each cylinder. If the change of interval time exceeds the preprogrammed criteria, the PCM detects a misfire in the corresponding cylinder. While the engine is running, the PCM counts 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, the PCM determines that a misfire, which can damage catalytic converter or affect emission performance, has occurred. Diagnostic support note This is a continuous monitor (Misfire). MIL illuminates if the PCM detects the misfire which affects emission performance 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 the misfire which can damage the catalytic converter during first drive cycle. PENDING CODE is available if the PCM detects the misfire which affects emission performance during first drive cycle. FREEZE FRAME DATA is available. DTC is stored in the PCM memory.
POSSIBLE CAUSE	Spark plug malfunction Ignition coil malfunction Ignition system malfunction Fuel injector malfunction Air suction in intake air system (between dynamic chamber and cylinder head) Inadequate engine compression due to engine internal malfunction Related connector or terminal malfunction Related wiring harness malfunction

DTC P0301
DTC P0302
DTC P0303
DTC P0304

Cylinder No. 1 misfire detected
Cylinder No. 2 misfire detected
Cylinder No. 3 misfire detected
Cylinder No. 4 misfire detected

DETECTION CONDITION

The PCM monitors CKP sensor input signal interval time. The PCM calculates the change of interval time for each cylinder. If the change of interval time exceeds the preprogrammed criteria, the PCM detects a misfire in the corresponding cylinder. While the engine is running, the PCM counts 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, the PCM determines that a misfire, which can damage catalytic converter or affect emission performance, has occurred.

Diagnostic support note

This is a continuous monitor (Misfire).
MIL illuminates if the PCM detects the misfire which affects emission performance 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 the misfire which can damage the catalytic converter during first drive cycle.
PENDING CODE is available if the PCM detects the misfire which affects emission performance during first drive cycle.
FREEZE FRAME DATA is available.
DTC is stored in the PCM memory.

POSSIBLE CAUSE

Spark plug malfunction
Ignition coil malfunction
Ignition system malfunction
Fuel injector malfunction
Air suction in intake air system (between dynamic chamber and cylinder head)
Inadequate engine compression due to engine internal malfunction
Related connector or terminal malfunction
Related wiring harness malfunction