P0300 — Random/Multiple Cylinder Misfire Detected
Category: Powertrain Severity: High
Updated:
DTC code P0300 means: Random/Multiple Cylinder Misfire Detected. It falls under the "Powertrain" category, with an estimated severity of High. Common causes include faulty spark plugs or ignition coils, vacuum leak and faulty fuel injector(s); it's worth confirming the diagnosis before replacing parts.
Possible causes
- Faulty spark plugs or ignition coils
- Vacuum leak
- Faulty fuel injector(s)
- Low compression
- Incorrect cam/crank timing
Symptoms
- Engine vibration
- Loss of power
- Higher fuel consumption
- Engine may not start
How to diagnose it step by step
- Read per-cylinder misfire counters to see whether one or several cylinders are affected.
- Check spark plugs (wear, gap) and coils.
- Look for vacuum leaks if several cylinders misfire.
- Check fuel pressure and injectors.
- Do a compression test if it persists.
How to fix it
Check spark plugs, coils and position sensors (crankshaft/camshaft); replace any faulty part.
Estimated repair cost
Spark plugs: $50–200. Coil: $60–220. Injector: $100–400.
Frequently asked questions
What does DTC code P0300 mean?
Random/Multiple Cylinder Misfire Detected.
Is code P0300 serious?
Severity High. Have it checked as soon as possible, especially if it affects safety or the catalytic converter.
Can I keep driving with code P0300?
If the check engine light is flashing, no: unburned fuel can melt the catalytic converter. If it's steady, drive gently to the workshop.
Related codes
P0301 P0302 P0303 P0304 P0305 P0306 P0307 P0308 P0316 P0320
Refine by car make
- Audi P0300: Individual coil packs and spark plugs (TFSI engines).
- BMW P0300: Coils and spark plugs; rule out intake vacuum leaks.
- Citroën P0300: Spark plugs, coils, or position sensor.
- Dacia P0300: Same as Renault: spark plugs, coils, or injectors.
- Fiat P0300: Spark plugs and coils; check the wiring.
- Ford P0300: Faulty coil-on-plug (COP) ignition coils; also check the spark plugs.
- Honda P0300: Spark plugs, coils, or injectors.
- Hyundai P0300: Coils or spark plugs.
- Kia P0300: Coils or spark plugs.
- Mazda P0300: Coils or spark plugs.
- Mercedes-Benz P0300: Spark plugs, coils, or injectors; check the ignition system.
- Nissan P0300: Coils, spark plugs, or injectors.
- Opel P0300: Ignition coil; check the ignition module.
- Peugeot P0300: Spark plugs, coils, or injectors (on HDI, check the injectors).
- Renault P0300: Spark plugs, coils, or injectors (on dCi, check the injectors).
- Seat P0300: Same as VW: individual coil packs and spark plugs.
- Škoda P0300: Same as VW: individual coil packs and spark plugs.
- Toyota P0300: Spark plugs, coils, and injectors.
- Volkswagen P0300: Individual coil packs (very common on TSI engines) and spark plugs.
- Volvo P0300: Coils, spark plugs, or injectors.
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