P0304

DTC P0304 CYLINDER 4 MISFIRE DETECTED

CIRCUIT DESCRIPTION
ECM measures the angle speed of the crankshaft based on the pulse signal from the CKP sensor and CMP sensor for each cylinder. If it detects a large change in the angle speed of the crankshaft, it concludes occurrence of a misfire. When the number of misfire is counted by the ECM beyond the DTC detecting condition, it determines the cylinder where the misfire occurred and outputs it as DTC.





DETECTING CONDITION

DTC CONFIRMATION PROCEDURE

WARNING:
- When performing a road test, select a place where there is no traffic or possibility of a traffic accident and be very careful during testing to avoid occurrence of an accident.
- Road test should be carried out with 2 persons, a driver and a tester, on a level road.

NOTE: Check to make sure that following conditions are satisfied when using this DTC CONFIRMATION PROCEDURE.
- Fuel level : higher than 1/4 (fuel level meter indication).
- Intake air temp.: -14°C, 6.8°F or higher.
- Atmospheric pressure (Altitude) : 540 mmHg, 72 kPa or more (2790m, 9150 ft or less).

1) Connect scan tool to DLC with ignition switch OFF
2) Turn ON ignition switch and clear DTC, pending DTC and freeze frame data by using scan tool.
3) Start engine and run it at idle speed to warm up completely.
4) Increase vehicle speed to speed recorded as freeze frame data (V) ± 5km/h when detecting misfire.
5) Keep driving above vehicle speed for 1 min.
6) Release accelerator pedal, stop vehicle and check pending DTC and DTC by using scan tool.

PAGE REFERENCE:

TROUBLESHOOTING