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P0304: Cylinder 4 Misfire Detected
Cylinder number 4 is misfiring.
High Severity
$50 – $500
Can I Keep Driving with Code P0304?
Avoid extended driving.
What P0304 Means
Cylinder 4 specific misfire. Same diagnosis as other single-cylinder misfires.
Common Causes
- Bad spark plug in cylinder 4 — see repair cost
- Failed ignition coil on cylinder 4
- Clogged fuel injector — see repair cost
- Low compression
Diagnostic Tips
- Try the coil swap diagnostic.
- Replace plugs as a set if mileage is high.
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Get My Free EstimateFrequently Asked Questions
On a 4-cylinder engine, where is cylinder 4?
Usually the cylinder furthest from the timing belt or chain end of the engine.