p0300
Moderate
Mazda · Sedans
Random/Multiple Cylinder Misfire Detected
Quick Answer
Error code P0300 on your Mazda Sedans means: Random/Multiple Cylinder Misfire Detected. This is usually fixable — see the step-by-step guide below.
Affected Models
Applies to all models
NCBLGHSE
Likely Causes
  1. Faulty spark plugs
  2. Ignition coil failure
  3. Fuel injector issue
  4. Compression loss
  5. Contaminated fuel
How to Fix It
1
Retrieve specific misfire cylinders with scanner
2
Inspect and replace spark plugs if worn
3
Check ignition coil packs for continuity
4
Perform cylinder compression test
5
Clear codes and test drive to verify repair
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
Ignition coils
Fuel filter
Engine oil
Related Error Codes
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