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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 73–96 of 378
P04D0EGR Temperature Sensor C Circuit LowCheck soonEmissions System30–120 minutes for initial diagnosisP04D1EGR Temperature Sensor C Circuit HighCheck soonEmissions System30–120 minutes for initial diagnosisP04D2EGR Temperature Sensor C Circuit Intermittent/ErraticCheck soonEmissions System30–120 minutes for initial diagnosisP04D8Excessive Time To Enter Closed Loop EGR ControlCheck soonEmissions System30–120 minutes for initial diagnosisP04D9Closed Loop EGR Control At Limit - Flow Too LowCheck soonEmissions System30–120 minutes for initial diagnosisP04DAClosed Loop EGR Control At Limit - Flow Too HighCheck soonEmissions System30–120 minutes for initial diagnosisP04DDCold Start EGR A Flow Insufficient DetectedCheck soonEmissions System30–120 minutes for initial diagnosisP04DECold Start EGR A Flow Excessive DetectedCheck soonEmissions System30–120 minutes for initial diagnosisP04E5EGR Temperature Sensor D CircuitCheck soonEmissions System30–120 minutes for initial diagnosisP04E6EGR Temperature Sensor D Circuit Range/PerformanceCheck soonEmissions System30–120 minutes for initial diagnosisP04E7EGR Temperature Sensor D Circuit LowCheck soonEmissions System30–120 minutes for initial diagnosisP04E8EGR Temperature Sensor D Circuit HighCheck soonEmissions System30–120 minutes for initial diagnosisP04E9EGR Temperature Sensor D Circuit Intermittent/ErraticCheck soonEmissions System30–120 minutes for initial diagnosisP04F2Catalyst Heater Supply Voltage Bank 1Check soonEmissions System30–120 minutes for initial diagnosisP04F3Catalyst Heater Supply Voltage Bank 2Check soonEmissions System30–120 minutes for initial diagnosisP04F4Catalyst Heater Circuit Low Bank 1Check soonEmissions System30–120 minutes for initial diagnosisP04F5Catalyst Heater Circuit Low Bank 2Check soonEmissions System30–120 minutes for initial diagnosisP04F6Catalyst Heater Circuit High Bank 1Check soonEmissions System30–120 minutes for initial diagnosisP04F7Catalyst Heater Circuit High Bank 2Check soonEmissions System30–120 minutes for initial diagnosisP04F8Catalyst Heater Circuit Intermittent Bank 1Check soonEmissions System30–120 minutes for initial diagnosisP04F9Catalyst Heater Circuit Intermittent Bank 2Check soonEmissions System30–120 minutes for initial diagnosisP04FAEGR A Control Temperature Too HighCheck soonEmissions System30–120 minutes for initial diagnosisP04FDEGR Actuator A Control Processor PerformanceCheck soonEmissions System30–120 minutes for initial diagnosisP04FECatalyst Heater Circuit Performance Bank 1Check soonEmissions System30–120 minutes for initial diagnosis