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Home >> Hyundai >> 2012 >> Elantra Touring GLS, Standard Trans >> Repair and Diagnosis >> Engine Performance >> System >> DTC Troubleshooting Procedures >> Inspection Chart For Diagnostic Trouble Codes (DTC) >> P0300: Random/Multiple Cylinder Misfire Detected >> DTC Detecting Condition

P0300: Random/Multiple Cylinder Misfire Detected: DTC Detecting Condition

P0300 RANDOM/MULTIPLE CYLINDER MISFIRE DETECTED

Item Detecting Condition Possible Cause
DTC Strategy
  • Calculation of engine roughness
  • Faulty spark plugs, high-tension lead, or Ignition coil
  • Incorrect valve timing
  • Uneven compression
  • Air leakage
  • Improper Fuel pressure or dirty fuel.
  • Blocked/Leaking injectors
  • Leakage between cooling system and cylinder
Enable Conditions
  • 156 < Mass air flow (mg/rev.) < 710 (depends on RPM, Coolant temp.)
  • 512 < Engine speed (RPM) < 6500
  • 141 < Throttle gradient (°TPS/sec.) < 199
  • Coolant temperature > 20 °C (-4 °F) if Start temperature < -7 °C (19.4 °F)
  • No rough road
  • No relevant failure
  • 11 V< Battery voltage
  • Fuel cut off not active
Threshold Value
  • Misfire detected on 2 or more cylinders
Mil On Condition
  • When misfire rate is high enough to damage the catalyst : Immediate
  • When emissions level to exceed standard value : 2 Driving Cycles