P0300 SCION - Random Cylinder Misfire Condition

Repair Importance Level: 3/3
Repair Difficulty Level: 3/3  What does this mean?

P0300 SCION 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
  • Mass air flow meter
  • Engine coolant temperature sensor
  • Valve clearance
  • Valve timing
  • ECM

P0300 SCION 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"

Cost of diagnosing the P0300 SCION code

    Labor: 1.0

    The cost of diagnosing the P0300 SCION code is 1.0 hour of labor. The auto repair labor rates vary widely across the country, and even within the same city. Most auto repairs shops charge between $75 and $150 per hour.

When is the P0300 SCION code detected?

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

P0300 SCION Possible Symptoms

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

P0300 SCION Meaning

When the engine misfires, high concentrations of hydrocarbons (HC) enter the exhaust gas. Extremely high HC concentration levels can cause increases in exhaust emission levels. High concentrations of HC can also cause increases in the Three-Way Catalytic Converter (TWC) temperature, which may cause damage to the TWC. To prevent these increases in emissions and to limit the possibility of thermal damage, the ECM monitors the misfire rate. When the temperature of the TWC reaches the point of thermal degradation, the ECM blinks the MIL. To monitor misfires, the ECM uses both the Camshaft Position (CMP) sensor and the Crankshaft Position (CKP) sensor. The CMP sensor is used to identify any misfiring cylinders and the CKP sensor is used to measure variations in the crankshaft rotation speed. Misfires are counted when the crankshaft rotation speed variations exceed predetermined thresholds. If the misfire exceeds the threshold levels, and could cause emission deterioration, the ECM illuminates the MIL and sets a DTC.
OBDII Code P0300 SCION - Random Cylinder Misfire Condition - Engine-Codes.com

P0300 SCION Information for specific Scion models

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