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9,253 diagnostic guides
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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 361–384 of 515
P249BEGR Cooler Bypass Position Sensor Circuit Intermittent/Erratic Bank 2Check soonEmissions System30–120 minutes for initial diagnosisP249FExcessive Time To Enter Closed Loop Particulate Filter Regeneration ControlCheck soonEmissions System30–120 minutes for initial diagnosisP24A0Closed Loop Particulate Filter Regeneration Control At Limit - Temperature Too LowCheck soonEmissions System30–120 minutes for initial diagnosisP24A1Closed Loop Particulate Filter Regeneration Control At Limit - Temperature Too HighCheck soonEmissions System30–120 minutes for initial diagnosisP24A2Particulate Filter Regeneration Incomplete Bank 1Check soonEmissions System30–120 minutes for initial diagnosisP24A3Particulate Filter Restriction - Soot Accumulation Bank 2Check soonEmissions System30–120 minutes for initial diagnosisP24A4Particulate Filter Restriction - Soot Accumulation Too High Bank 1Check soonEmissions System30–120 minutes for initial diagnosisP24A5EGR Cooler Bypass Control Stuck/Open Bank 1Check soonEmissions System30–120 minutes for initial diagnosisP24A6EGR Cooler Bypass Control Stuck/Open Bank 2Check soonEmissions System30–120 minutes for initial diagnosisP24A7EGR Cooler Coolant Pump Control Circuit/OpenCheck soonEmissions System30–120 minutes for initial diagnosisP24A8EGR Cooler Coolant Pump Performance/Stuck OffCheck soonEmissions System30–120 minutes for initial diagnosisP24A9EGR Cooler Coolant Pump Control Circuit LowCheck soonEmissions System30–120 minutes for initial diagnosisP24AAEGR Cooler Coolant Pump Control Circuit HighCheck soonEmissions System30–120 minutes for initial diagnosisP24ABEGR Cooler Coolant Pump Stuck OnCheck soonEmissions System30–120 minutes for initial diagnosisP24ACEGR Cooler Coolant Pump Feedback Circuit LowCheck soonEmissions System30–120 minutes for initial diagnosisP24ADEGR Cooler Coolant Pump Feedback Circuit HighCheck soonEmissions System30–120 minutes for initial diagnosisP24AEParticulate Matter Sensor CircuitCheck soonEmissions System30–120 minutes for initial diagnosisP24AFParticulate Matter Sensor Circuit Range/PerformanceCheck soonEmissions System30–120 minutes for initial diagnosisP24B0Particulate Matter Sensor Circuit LowCheck soonEmissions System30–120 minutes for initial diagnosisP24B1Particulate Matter Sensor Circuit HighCheck soonEmissions System30–120 minutes for initial diagnosisP24B2Particulate Matter Sensor Circuit IntermittentCheck soonEmissions System30–120 minutes for initial diagnosisP24B3Particulate Matter Sensor Heater Control Circuit/OpenCheck soonEmissions System30–120 minutes for initial diagnosisP24B4Particulate Matter Sensor Heater Control Circuit Range/PerformanceCheck soonEmissions System30–120 minutes for initial diagnosisP24B5Particulate Matter Sensor Heater Control Circuit LowCheck soonEmissions System30–120 minutes for initial diagnosis