P0304Worn out spark plugs, ignition wires, coil(s), distributor cap and rotor (when applicable), Incorrect ignition timing, Vacuum leak(s), Low or weak fuel pressure, Improperly functioning EGR sy
El cilindro 4 no combustiona correctamente.
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Can I keep driving? With caution
You can drive to the shop, but do not postpone the repair. The problem may worsen and damage other components.
Sistema Afectado
Sistema de Encendido · Bujías, bobinas y cilindros
El problema afecta la combustión en uno o más cilindros: bujías, bobinas o inyectores.
Espacio para vendedores de repuestos
Aún no hay un anunciante en este espacio.
Symptoms You Will Notice
What you may observe when this code appears
- Vibración del motor
- Pérdida de potencia en cilindro 4
Possible Causes
The components or conditions that trigger this code
- 1Bujía cilindro 4 defectuosa
- 2Bobina de encendido dañada
How to Fix It — Step by Step
Recommended diagnostic and repair procedure
- 1Reemplazar bujía cilindro
- 2Probar bobina.
Note: This information is for general reference. For precise diagnostics and safety repairs, always consult a certified mechanic.
Estimated Cost
Approximate range in USD (varies by region and shop)
Spark plugs + coils
* Diagnosis only: $50–$150
Quick Info
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