Engine-Codes - Subaru - P0300 Subaru

P0300 Subaru Code - Random Cylinder Misfire Detected

- Code Popularity: 36,713 Views
- Repair Importance Level: 3/3
- Repair Difficulty Level: 3/3
Table of contents

What are the Possible Causes of the Code P0300 Subaru?

  • 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 to Fix the P0300 Subaru Code?

Start by checking 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.

Code P0300 Subaru Tech Notes

The P0300 code means that a cylinder(s) is misfiring or is randomly misfiring. Start by checking for intake leaks, intake gaskets are common caused of multi-cylinder misfiring. If no leak are found the next step is to replace the spark plugs. If the problem persists more tests needs to be done to diagnose problem, see "Possible Causes"

What is the Cost to Diagnose the Code P0300 Subaru?

Labor: 1.0

The cost to diagnose the P0300 Subaru code is 1.0 hour of labor. The auto repair's diagnosis time and labor rates vary by location, vehicle's make and model, and even your engine type. Most auto repair shops charge between $75 and $150 per hour.

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When is the P0300 Subaru Code Detected?

The control module monitors the crankshaft speed and has detected a misfire condition

What are Code P0300 Subaru Possible Symptoms?

  • Engine Light ON (or Service Engine Soon Warning Light)
  • Lack/loss of power
  • Hard start
  • Engine hesitation

What Does the P0300 Subaru Code Mean?

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.

P0300 Subaru Code - Random Cylinder Misfire Detected

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