System: Ignition & Misfire · Standard: SAE J2012 generic code · Severity: Do not keep driving
This fault can damage expensive hardware within a short distance. Stop and diagnose before driving further.
Same diagnostic approach as any single-cylinder misfire: isolate ignition first, then fuel, then compression.
Start by reading every stored and pending code, not just this one. A single fault frequently sets three or four codes at once, and the first one in the freeze-frame data is usually the cause while the rest are consequences.
The controller has identified repeated misfires on cylinder 4. Cylinder 4 Misfire Detected is a generic ignition & misfire code defined by SAE J2012, so it carries the same meaning on every OBD-II vehicle.
Do not keep driving. This fault can damage expensive hardware within a short distance. Stop and diagnose before driving further.
In rough order of how often they turn out to be the problem: Failed spark plug on cylinder 4; Failed ignition coil; Faulty injector.
P0300 Random or Multiple Cylinder Misfire DetectedP0301 Cylinder 1 Misfire DetectedP0302 Cylinder 2 Misfire DetectedP0303 Cylinder 3 Misfire DetectedP0305 Cylinder 5 Misfire DetectedP0306 Cylinder 6 Misfire DetectedCode number, system and definition follow the SAE J2012 / ISO 15031-6 generic diagnostic trouble code standard. Symptoms, causes and severity are the standard generic diagnostic logic for that fault. This page does not contain manufacturer-specific procedures, part numbers or pricing.