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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 169–192 of 378
P23E7EGR C Flow Insufficient DetectedCheck soonEmissions System30–120 minutes for initial diagnosisP23E8EGR C Flow Excessive DetectedCheck soonEmissions System30–120 minutes for initial diagnosisP240FEGR Slow ResponseCheck soonEmissions System30–120 minutes for initial diagnosisP2413EGR System PerformanceCheck soonEmissions System30–120 minutes for initial diagnosisP241FEGR Cooler B Efficiency Below ThresholdCheck soonEmissions System30–120 minutes for initial diagnosisP2425EGR Cooling Valve Control Circuit/OpenCheck soonEmissions System30–120 minutes for initial diagnosisP2426EGR Cooling Valve Control Circuit LowCheck soonEmissions System30–120 minutes for initial diagnosisP2427EGR Cooling Valve Control Circuit HighCheck soonEmissions System30–120 minutes for initial diagnosisP2428Exhaust Gas Temperature Too High Bank 1Check soonEmissions System30–120 minutes for initial diagnosisP2429Exhaust Gas Temperature Too High Bank 2Check soonEmissions System30–120 minutes for initial diagnosisP242AExhaust Gas Temperature Sensor Circuit Bank 1 Sensor 3Check soonEmissions System30–120 minutes for initial diagnosisP242BExhaust Gas Temperature Sensor Circuit Range/Performance Bank 1 Sensor 3Check soonEmissions System30–120 minutes for initial diagnosisP242CExhaust Gas Temperature Sensor Circuit Low Bank 1 Sensor 3Check soonEmissions System30–120 minutes for initial diagnosisP242DExhaust Gas Temperature Sensor Circuit High Bank 1 Sensor 3Check soonEmissions System30–120 minutes for initial diagnosisP242EExhaust Gas Temperature Sensor Circuit Intermittent/Erratic Bank 1 Sensor 3Check soonEmissions System30–120 minutes for initial diagnosisP242FParticulate Filter Restriction - Ash Accumulation Bank 1Check soonEmissions System30–120 minutes for initial diagnosisP243AParticulate Filter Restriction - Ash Accumulation Bank 2Check soonEmissions System30–120 minutes for initial diagnosisP243BParticulate Filter Restriction - Forced Limited Power Bank 2Check soonEmissions System30–120 minutes for initial diagnosisP243CParticulate Filter Regeneration Frequency Bank 2Check soonEmissions System30–120 minutes for initial diagnosisP243DParticulate Filter Regeneration Duration Bank 2Check soonEmissions System30–120 minutes for initial diagnosisP243EParticulate Filter Regeneration Incomplete Bank 2Check soonEmissions System30–120 minutes for initial diagnosisP243FParticulate Filter Restriction - Soot Accumulation Too High Bank 2Check soonEmissions System30–120 minutes for initial diagnosisP244AParticulate Filter Differential Pressure Too Low Bank 1Check soonEmissions System30–120 minutes for initial diagnosisP244BParticulate Filter Differential Pressure Too High Bank 1Check soonEmissions System30–120 minutes for initial diagnosis