P0304
Cylinder 4 Misfire Detected
Generic code
Ignition System
High severity
Hard repair
Free on OBD DashX
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What P0304 means
- The fault code P0304 indicates that there is a misfire detected in the cylinder 4 of the engine. This may result in poor engine performance, reduced fuel efficiency, and increased emissions.
Possible symptoms
- Illuminated check engine light
- Rough idle or stalling
- Reduced engine power or acceleration
- Vibrations or shaking while driving
- Increased fuel consumption
- Increased exhaust emissions
Possible causes
- Faulty spark plug in cylinder 4
- Failed ignition coil in cylinder 4
- Low compression in cylinder 4
- Malfunctioning fuel injector in cylinder 4
- Vacuum leak in the intake manifold
- Failed engine control module (ECM)
Related parts
- Crankshaft Position Sensor: The crankshaft position sensor monitors the position of the crankshaft to regulate fuel injection. Problems lead to engine misfire and engine stalling
Possible solutions
- Replace the spark plug in cylinder 4
- Replace the ignition coil in cylinder 4
- Check and repair any low compression issues in cylinder 4
- Replace the fuel injector in cylinder 4
- Inspect and repair any vacuum leaks in the intake manifold
- Replace the engine control module (ECM) if necessary
Free on OBD DashX
P0304 on OBD DashX
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