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Most-searched fault codes
P0420 — Catalyst System Efficiency Below Threshold (Bank 1)P0171 — System Too Lean (Bank 1)P0300 — Random/Multiple Cylinder Misfire DetectedP0301 — Cylinder 1 Misfire DetectedP0174 — System Too Lean (Bank 2)P0455 — EVAP System Leak Detected (Large Leak)P0442 — EVAP System Leak Detected (Small Leak)P0401 — EGR Insufficient Flow DetectedP0128 — Coolant Thermostat (Below Regulating Temperature)P0101 — Mass Air Flow Sensor Range/PerformanceP0430 — Catalyst System Efficiency Below Threshold (Bank 2)P0440 — EVAP System Malfunction (General)P0135 — O2 Sensor Heater Circuit Malfunction (Bank 1, Sensor 1)P0141 — O2 Sensor Heater Circuit Malfunction (Bank 1, Sensor 2)P0402 — EGR Excessive Flow DetectedP0700 — Transmission Control System MalfunctionP0340 — Camshaft Position Sensor Circuit MalfunctionP0335 — Crankshaft Position Sensor Circuit MalfunctionP0130 — O2 Sensor Circuit Malfunction (Bank 1, Sensor 1)P2195 — O2 Sensor Signal Stuck Lean (Bank 1, Sensor 1)P0011 — "A" Camshaft Position — Timing Over-Advanced (Bank 1)P0014 — "B" Camshaft Position — Timing Over-Advanced (Bank 1)P0325 — Knock Sensor Circuit Malfunction (Bank 1)P0118 — Engine Coolant Temperature Sensor Circuit HighP2187 — System Too Lean at Idle (Bank 1)P0500 — Vehicle Speed Sensor (VSS) MalfunctionP0131 — O2 Sensor Circuit Low Voltage (Bank 1, Sensor 1)P0137 — O2 Sensor Circuit Low Voltage (Bank 1, Sensor 2)P0133 — O2 Sensor Slow Response (Bank 1, Sensor 1)P0021 — "A" Camshaft Position — Timing Over-Advanced (Bank 2)P0117 — Engine Coolant Temperature Sensor Circuit LowP2189 — System Too Lean at Idle (Bank 2)P2293 — Fuel Pressure Regulator 2 PerformanceU0100 — Lost Communication With ECM/PCM "A"P0012 — "A" Camshaft Position — Timing Over-Retarded (Bank 1)P0341 — Camshaft Position Sensor "A" Circuit Range/Performance (Bank 1)P0113 — Intake Air Temperature Sensor 1 Circuit High (Bank 1)P0506 — Idle Air Control System RPM Lower Than ExpectedP0507 — Idle Air Control System RPM Higher Than ExpectedP0456 — EVAP System Leak Detected (Very Small Leak)P0302 — Cylinder 2 Misfire DetectedP0303 — Cylinder 3 Misfire DetectedP0304 — Cylinder 4 Misfire DetectedP0172 — System Too Rich (Bank 1)P0102 — Mass Air Flow (MAF) Circuit Low InputP0299 — Turbocharger / Supercharger "A" UnderboostP0087 — Fuel Rail / System Pressure Too LowP0520 — Engine Oil Pressure Sensor / Switch CircuitP0103 — Mass Air Flow (MAF) Circuit High InputP0112 — Intake Air Temperature Sensor 1 Circuit Low (Bank 1)P0116 — Engine Coolant Temperature Sensor Circuit Range/PerformanceP0125 — Insufficient Coolant Temperature for Closed-Loop Fuel ControlP0016 — Crankshaft / Camshaft Position Correlation (Bank 1, Sensor A)P0446 — EVAP System Vent Control Circuit MalfunctionP0449 — EVAP System Vent Valve / Solenoid Circuit MalfunctionP0741 — Torque Converter Clutch Circuit Performance / Stuck OffP0562 — System Voltage LowP0563 — System Voltage HighP0234 — Turbocharger / Supercharger "A" Overboost ConditionP0327 — Knock Sensor 1 Circuit Low (Bank 1)P0106 — MAP / Barometric Pressure Circuit Range/PerformanceP0107 — MAP / Barometric Pressure Circuit Low InputP0108 — MAP / Barometric Pressure Circuit High InputP0121 — Throttle / Pedal Position Sensor "A" Circuit Range/PerformanceP0122 — Throttle / Pedal Position Sensor "A" Circuit Low InputP0123 — Throttle / Pedal Position Sensor "A" Circuit High InputP0443 — EVAP Purge Control Valve Circuit MalfunctionP0444 — EVAP Purge Control Valve Circuit OpenP0155 — O2 Sensor Heater Circuit Malfunction (Bank 2, Sensor 1)P0160 — O2 Sensor Circuit No Activity Detected (Bank 2, Sensor 2)
More flagship codes (P0174, P0455, P0442, P0401, P0128, P0101…) are being published — prioritized by real-world fault frequency.
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Engine MisfireRough IdleCheck Engine Light FlashingLoss of PowerPoor Fuel EconomyEngine StallingHard StartingEngine OverheatingCar Won’t Start (Battery OK)Engine KnockingWhite Smoke From ExhaustBlack Smoke From ExhaustTransmission SlippingCar Shaking at IdleHigh Idle RPMJerking During AccelerationFuel Smell in the CarCold-Start StallingSlow Acceleration / Lack of PowerVibration While Driving