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9,253 diagnostic guides
Find codes by symptomChoose what you notice to search matching code guides.
Rough idle or shakingVibration while stoppedHard to startLong cranking or no-startEngine stallsCuts out at idle or on the roadHesitates or loses powerSlow response when acceleratingBattery light is onCharging system warningHarsh gear changesDelayed or rough shifting
A symptom can have several causes. Treat matching codes as clues and follow the diagnostic checks in each guide.
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These are generic OBD2 definitions. Exact make, model, engine, and year compatibility will appear after vehicle-fitment data is added.
Diagnostic codes
Showing 1–24 of 7353
P0051Heated Oxygen Sensor Heater Control Circuit Low Bank 2 Sensor 1Low prioritySensors & Electronics45–120 minutes for initial diagnosisP0057Heated Oxygen Sensor Heater Control Circuit Low Bank 2 Sensor 2Low prioritySensors & Electronics45–120 minutes for initial diagnosisP0069Manifold Absolute Pressure–Barometric Pressure CorrelationCheck soonSensors & Electronics45–120 minutes for initial diagnosisP0089Fuel Pressure Regulator 1 PerformanceCheck soonFuel System45–120 minutes for initial diagnosisP0093Fuel System Leak Detected — Large LeakUrgentFuel System1–3 hours for initial diagnosisP0128Coolant Thermostat Below Regulating TemperatureCheck soonEngine Problems30–75 minutesP0130O2 Sensor Circuit Malfunction Bank 1 Sensor 1Sensors & ElectronicsP0171System Too Lean Bank 1 - Complete GuideCheck soonFuel System45–120 minutesP0172System Too Rich Bank 1 - Causes & SolutionsFuel SystemP0217Engine Overtemperature ConditionUrgentEngine Problems1–3 hours for initial diagnosisP0218Transmission Fluid Overtemperature ConditionUrgentTransmission Issues1–3 hours for initial diagnosisP0221Throttle/Pedal Position Sensor/Switch B Circuit Range/PerformanceCheck soonSensors & Electronics45–120 minutes for initial diagnosisP0235Turbocharger/Supercharger Boost Sensor A CircuitCheck soonSensors & Electronics45–120 minutes for initial diagnosisP0304Cylinder 4 Misfire Detected - Causes & FixesUrgentEngine Problems30–75 minutesP0335Crankshaft Position Sensor Circuit MalfunctionSensors & ElectronicsP0340Camshaft Position Sensor Circuit MalfunctionSensors & ElectronicsP0420Catalyst System Efficiency Below ThresholdLow priorityEmissions System60–150 minutesP0442EVAP System Small Leak DetectedLow priorityEmissions System30–120 minutesP0455EVAP System Large Leak DetectedEmissions SystemP0756Shift Solenoid B Performance or Stuck OffCheck soonTransmission Issues45–120 minutes for initial diagnosisP0760Shift Solenoid C MalfunctionCheck soonTransmission Issues45–120 minutes for initial diagnosisP0005Fuel Shutoff Valve A Control Circuit/OpenCheck soonFuel System30–120 minutes for initial diagnosisP0006Fuel Shutoff Valve A Control Circuit LowCheck soonFuel System30–120 minutes for initial diagnosisP0007Fuel Shutoff Valve A Control Circuit HighCheck soonFuel System30–120 minutes for initial diagnosis