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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 49–72 of 305
P0444Evaporative Emission Control System Purge Control Valve Circuit OpenLow priorityEmissions System30–120 minutes for initial diagnosisP0445Evaporative Emission Control System Purge Control Valve Circuit ShortedLow priorityEmissions System30–120 minutes for initial diagnosisP0447Evaporative Emission Control System Vent Control Circuit OpenLow priorityEmissions System30–120 minutes for initial diagnosisP0448Evaporative Emission Control System Vent Control Circuit ShortedLow priorityEmissions System30–120 minutes for initial diagnosisP0450Evaporative Emission Control System Pressure Sensor MalfunctionLow priorityEmissions System30–120 minutes for initial diagnosisP0453Evaporative Emission Control System Pressure Sensor High InputLow priorityEmissions System30–120 minutes for initial diagnosisP0454Evaporative Emission Control System Pressure Sensor IntermittentLow priorityEmissions System30–120 minutes for initial diagnosisP0458EVAP System Purge Control Valve A Circuit LowLow priorityEmissions System30–120 minutes for initial diagnosisP0459EVAP System Purge Control Valve A Circuit HighLow priorityEmissions System30–120 minutes for initial diagnosisP0460Fuel Level Sensor Circuit MalfunctionLow priorityFuel System30–120 minutes for initial diagnosisP0461Fuel Level Sensor Circuit Range/PerformanceLow priorityFuel System30–120 minutes for initial diagnosisP0462Fuel Level Sensor Circuit Low InputLow priorityFuel System30–120 minutes for initial diagnosisP0464Fuel Level Sensor Circuit IntermittentLow priorityFuel System30–120 minutes for initial diagnosisP0465Purge Flow Sensor Circuit MalfunctionLow priorityEmissions System30–120 minutes for initial diagnosisP0466Purge Flow Sensor Circuit Range/PerformanceLow priorityEmissions System30–120 minutes for initial diagnosisP0467Purge Flow Sensor Circuit Low InputLow priorityEmissions System30–120 minutes for initial diagnosisP0468Purge Flow Sensor Circuit High InputLow priorityEmissions System30–120 minutes for initial diagnosisP0469Purge Flow Sensor Circuit IntermittentLow priorityEmissions System30–120 minutes for initial diagnosisP0496Evaporative Emission System High Purge FlowLow priorityEmissions System30–120 minutes for initial diagnosisP0497Evaporative Emission System Low Purge FlowLow priorityEmissions System30–120 minutes for initial diagnosisP0498Evaporative Emission System Vent Valve Control Circuit LowLow priorityEmissions System30–120 minutes for initial diagnosisP0499Evaporative Emission System Vent Valve Control Circuit HighLow priorityEmissions System30–120 minutes for initial diagnosisP04ABEVAP System Purge Control Valve B Circuit/OpenLow priorityEmissions System30–120 minutes for initial diagnosisP04ACEVAP System Purge Control Valve B Circuit LowLow priorityEmissions System30–120 minutes for initial diagnosis