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Find codes by symptomChoose what you notice to search matching code guides.

Rough idle or shakingVibration while stopped Hard to startLong cranking or no-start Engine stallsCuts out at idle or on the road Hesitates or loses powerSlow response when accelerating Battery light is onCharging system warning Harsh gear changesDelayed or rough shifting

A symptom can have several causes. Treat matching codes as clues and follow the diagnostic checks in each guide.

Emissions System Clear all

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Engine1049 Emissions515 Fuel1016 Sensors & Electronics2110 Transmission866 Electrical & Charging1797 Body & Restraints193 Chassis & Brakes479 Network & Communication1228

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All severities9253 Low priority305 Check soon8256 Urgent621

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All families9253 P · Powertrain7353 B · Body193 C · Chassis479 U · Network1228

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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 121–144 of 515

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P04D9Closed Loop EGR Control At Limit - Flow Too LowCheck soonEmissions System30–120 minutes for initial diagnosisP04D9 relates to closed loop egr control at limit - flow too low. Check the fault conditions and vehicle-specific procedure before replacing parts.P04DAClosed Loop EGR Control At Limit - Flow Too HighCheck soonEmissions System30–120 minutes for initial diagnosisP04DA relates to closed loop egr control at limit - flow too high. Check the fault conditions and vehicle-specific procedure before replacing parts.P04DDCold Start EGR A Flow Insufficient DetectedCheck soonEmissions System30–120 minutes for initial diagnosisP04DD relates to cold start egr a flow insufficient detected. Check the fault conditions and vehicle-specific procedure before replacing parts.P04DECold Start EGR A Flow Excessive DetectedCheck soonEmissions System30–120 minutes for initial diagnosisP04DE relates to cold start egr a flow excessive detected. Check the fault conditions and vehicle-specific procedure before replacing parts.P04DFEVAP System Purge Control Valve A Performance/Stuck OpenLow priorityEmissions System30–120 minutes for initial diagnosisP04DF relates to evap system purge control valve a performance/stuck open. Check the fault conditions and vehicle-specific procedure before replacing parts.P04E0EVAP System Purge Control Valve A Stuck ClosedLow priorityEmissions System30–120 minutes for initial diagnosisP04E0 relates to evap system purge control valve a stuck closed. Check the fault conditions and vehicle-specific procedure before replacing parts.P04E5EGR Temperature Sensor D CircuitCheck soonEmissions System30–120 minutes for initial diagnosisP04E5 relates to egr temperature sensor d circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.P04E6EGR Temperature Sensor D Circuit Range/PerformanceCheck soonEmissions System30–120 minutes for initial diagnosisP04E6 relates to egr temperature sensor d circuit range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P04E7EGR Temperature Sensor D Circuit LowCheck soonEmissions System30–120 minutes for initial diagnosisP04E7 relates to egr temperature sensor d circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P04E8EGR Temperature Sensor D Circuit HighCheck soonEmissions System30–120 minutes for initial diagnosisP04E8 relates to egr temperature sensor d circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P04E9EGR Temperature Sensor D Circuit Intermittent/ErraticCheck soonEmissions System30–120 minutes for initial diagnosisP04E9 relates to egr temperature sensor d circuit intermittent/erratic. Check the fault conditions and vehicle-specific procedure before replacing parts.P04EAEVAP System Small Leak Detected - Fuel Tank SideLow priorityEmissions System30–120 minutes for initial diagnosisP04EA relates to evap system small leak detected - fuel tank side. Check the fault conditions and vehicle-specific procedure before replacing parts.P04EBEVAP System Small Leak Detected - Fresh Air SideLow priorityEmissions System30–120 minutes for initial diagnosisP04EB relates to evap system small leak detected - fresh air side. Check the fault conditions and vehicle-specific procedure before replacing parts.P04ECEVAP System Large Leak Detected - Fuel Tank SideLow priorityEmissions System30–120 minutes for initial diagnosisP04EC relates to evap system large leak detected - fuel tank side. Check the fault conditions and vehicle-specific procedure before replacing parts.P04EDEVAP System Large Leak Detected - Fresh Air SideLow priorityEmissions System30–120 minutes for initial diagnosisP04ED relates to evap system large leak detected - fresh air side. Check the fault conditions and vehicle-specific procedure before replacing parts.P04EEEVAP System Very Small Leak Detected - Fuel Tank SideLow priorityEmissions System30–120 minutes for initial diagnosisP04EE relates to evap system very small leak detected - fuel tank side. Check the fault conditions and vehicle-specific procedure before replacing parts.P04EFEVAP System Very Small Leak Detected - Fresh Air SideLow priorityEmissions System30–120 minutes for initial diagnosisP04EF relates to evap system very small leak detected - fresh air side. Check the fault conditions and vehicle-specific procedure before replacing parts.P04F0EVAP System High Load Purge Line A PerformanceLow priorityEmissions System30–120 minutes for initial diagnosisP04F0 relates to evap system high load purge line a performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P04F1EVAP System Purge Line PerformanceLow priorityEmissions System30–120 minutes for initial diagnosisP04F1 relates to evap system purge line performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P04F2Catalyst Heater Supply Voltage Bank 1Check soonEmissions System30–120 minutes for initial diagnosisP04F2 relates to catalyst heater supply voltage bank 1. Check the fault conditions and vehicle-specific procedure before replacing parts.P04F3Catalyst Heater Supply Voltage Bank 2Check soonEmissions System30–120 minutes for initial diagnosisP04F3 relates to catalyst heater supply voltage bank 2. Check the fault conditions and vehicle-specific procedure before replacing parts.P04F4Catalyst Heater Circuit Low Bank 1Check soonEmissions System30–120 minutes for initial diagnosisP04F4 relates to catalyst heater circuit low bank 1. Check the fault conditions and vehicle-specific procedure before replacing parts.P04F5Catalyst Heater Circuit Low Bank 2Check soonEmissions System30–120 minutes for initial diagnosisP04F5 relates to catalyst heater circuit low bank 2. Check the fault conditions and vehicle-specific procedure before replacing parts.P04F6Catalyst Heater Circuit High Bank 1Check soonEmissions System30–120 minutes for initial diagnosisP04F6 relates to catalyst heater circuit high bank 1. Check the fault conditions and vehicle-specific procedure before replacing parts.