Random/Multiple Cylinder Misfire Detected
Table of contents
- Possible Causes
- How To Fix
- Tech Notes
- Cost To Diagnose
- When is the code detected
- Possible Symptoms
- Description
P0300 KIA 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
How do I fix code P0300 KIA?
Check the “Possible Causes” listed above. Visually inspect the related wiring harness and connectors. Check for damaged components and look for broken, bent, pushed out, or corroded connector’s pins.
Tech Notes
- There is a factory service bulletin for the following KIA models:
- Kia Rio (JB)
- Kia Soul (AM)
- Kia Optima (MG)
- Kia Rondo (UN)
- Kia Forte (TD)
- Kia Spectra (LD)
- Kia Sportage (KM)
- Kia Optima (MG)
- Kia Sedona (VQ)
- Kia Amanti (GH)
- Kia Borrego (HM)
- Kia Sedona (VQ)
- Kia Sorento (BL)
- Kia Borrego (HM)
- The bulletin provides information on how to inspect and diagnose problems related to the Oil Control Valve (OCV) used in Constant Variable Valve Timing (CVVT), if at any time the OCV is suspected as the caused of rough idling, poor acceleration, camshaft timing misalignment-related trouble codes, misfire-related trouble codes.
- Factory Service Bulletin: Kia Constant Variable Valve Timing Oil Control Valve Inspection OBDII Code P0300
Cost of diagnosing the P0300 KIA code
The cost of diagnosing the P0300 KIA code is 1.0 hour of labor. The auto repair labor rates vary by location, your vehicle’s make and model, and even your engine type. Most auto repairs shops charge between $75 and $150 per hour.
When is the code detected
The control module monitors the crankshaft speed and has detected a misfire condition
Possible Symptoms
- Engine Light ON (or Service Engine Soon Warning Light)
- Lack/loss of power
- Hard start
- Engine hesitation
P0300 KIA Description
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.