p0300
Moderate
Honda · Sedans
Random/Multiple Cylinder Misfire Detected
Quick Answer
Error code P0300 on your Honda Sedans means: Random/Multiple Cylinder Misfire Detected. This is usually fixable — see the step-by-step guide below.
Affected Models
Applies to all models
CV3CV4FC1FC4FE1FL5ZC5Accord EX 2024Accord EX-L 2024Accord Hybrid EX-L 2024Accord Hybrid Sport 2024Accord Hybrid Touring 2024Accord LX 2024Accord Sport 2024Accord Touring 2024Civic EX 2024Civic Hybrid Sport 2025Civic Hybrid Sport Touring 2025Civic LX 2024Civic Si 2024Civic Sport 2024Civic Touring 2024Civic Type R 2024ZE4
Likely Causes
How to Fix It
1
Pull and inspect all spark plugs for wear, fouling, or incorrect gap; replace as a set if needed
2
Test each ignition coil with a multimeter or swap coils between cylinders to isolate a failure
3
Check fuel pressure at the rail and inspect injectors for proper spray pattern
4
Perform a vacuum leak test using a smoke machine
5
Run a compression test on all cylinders to rule out internal engine issues
Pro Tip
This fix requires some technical knowledge. If you're unsure about any step, consider contacting support or a qualified technician.
Parts You May Need
Spark plugs (NGK or Denso OEM-spec)
Ignition coil packs
Fuel injectors
Intake manifold gasket
Valve cover gasket
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