P0300 Code: Meaning, Causes, and Symptoms | OBD2 Codes

P0300 – Cylinder Misfire Detected Random Cylinders

P0300 Possible Causes

Faulty spark plug (s)

Faulty ignition coil (s)

Clogged or faulty fuel injector (s)

Intake air leak

Fuel injectors harness is open or shorted

Fuel Injectors circuit poor electrical connection

Ignition coils harness is open or shorted

Ignition coils circuit poor electrical connection

Insufficient cylinders compression

Incorrect fuel pressure

P0300 Possible Symptoms

Engine Light ON (or Service Engine Soon Warning Light)

Lack/loss of power

Hard start

Engine hesitation


When a misfire occurs, engine speed will fluctuate. If the engine speed fluctuates enough to cause the Crankshaft Position (CKP) sensor signal to vary, the Engine Control Module (ECM) can determine that a misfire is occurring.