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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.

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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 4537–4560 of 7353

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P23F4Cylinder 3 Injector B Air-Fuel Ratio ImbalanceCheck soonFuel System30–120 minutes for initial diagnosisP23F4 relates to cylinder 3 injector b air-fuel ratio imbalance. Check the fault conditions and vehicle-specific procedure before replacing parts.P23F5Cylinder 4 Injector B Air-Fuel Ratio ImbalanceCheck soonFuel System30–120 minutes for initial diagnosisP23F5 relates to cylinder 4 injector b air-fuel ratio imbalance. Check the fault conditions and vehicle-specific procedure before replacing parts.P23F6Cylinder 5 Injector B Air-Fuel Ratio ImbalanceCheck soonFuel System30–120 minutes for initial diagnosisP23F6 relates to cylinder 5 injector b air-fuel ratio imbalance. Check the fault conditions and vehicle-specific procedure before replacing parts.P23F7Cylinder 6 Injector B Air-Fuel Ratio ImbalanceCheck soonFuel System30–120 minutes for initial diagnosisP23F7 relates to cylinder 6 injector b air-fuel ratio imbalance. Check the fault conditions and vehicle-specific procedure before replacing parts.P23F8Cylinder 7 Injector B Air-Fuel Ratio ImbalanceCheck soonFuel System30–120 minutes for initial diagnosisP23F8 relates to cylinder 7 injector b air-fuel ratio imbalance. Check the fault conditions and vehicle-specific procedure before replacing parts.P23F9Cylinder 8 Injector B Air-Fuel Ratio ImbalanceCheck soonFuel System30–120 minutes for initial diagnosisP23F9 relates to cylinder 8 injector b air-fuel ratio imbalance. Check the fault conditions and vehicle-specific procedure before replacing parts.P23FACylinder 9 Injector B Air-Fuel Ratio ImbalanceCheck soonFuel System30–120 minutes for initial diagnosisP23FA relates to cylinder 9 injector b air-fuel ratio imbalance. Check the fault conditions and vehicle-specific procedure before replacing parts.P23FBCylinder 10 Injector B Air-Fuel Ratio ImbalanceCheck soonFuel System30–120 minutes for initial diagnosisP23FB relates to cylinder 10 injector b air-fuel ratio imbalance. Check the fault conditions and vehicle-specific procedure before replacing parts.P23FCCylinder 11 Injector B Air-Fuel Ratio ImbalanceCheck soonFuel System30–120 minutes for initial diagnosisP23FC relates to cylinder 11 injector b air-fuel ratio imbalance. Check the fault conditions and vehicle-specific procedure before replacing parts.P23FDCylinder 12 Injector B Air-Fuel Ratio ImbalanceCheck soonFuel System30–120 minutes for initial diagnosisP23FD relates to cylinder 12 injector b air-fuel ratio imbalance. Check the fault conditions and vehicle-specific procedure before replacing parts.P23FEBank 1 System B Air-Fuel Ratio ImbalanceCheck soonFuel System30–120 minutes for initial diagnosisP23FE relates to bank 1 system b air-fuel ratio imbalance. Check the fault conditions and vehicle-specific procedure before replacing parts.P23FFBank 2 System B Air-Fuel Ratio ImbalanceCheck soonFuel System30–120 minutes for initial diagnosisP23FF relates to bank 2 system b air-fuel ratio imbalance. Check the fault conditions and vehicle-specific procedure before replacing parts.P2400EVAP System Leak Detection Pump Control Circuit/OpenLow priorityEmissions System30–120 minutes for initial diagnosisP2400 relates to evap system leak detection pump control circuit/open. Check the fault conditions and vehicle-specific procedure before replacing parts.P2401EVAP System Leak Detection Pump Control Circuit LowLow priorityEmissions System30–120 minutes for initial diagnosisP2401 relates to evap system leak detection pump control circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P2402EVAP System Leak Detection Pump Control Circuit HighLow priorityEmissions System30–120 minutes for initial diagnosisP2402 relates to evap system leak detection pump control circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P2403EVAP System Leak Detection Pump Sense Circuit/OpenLow priorityEmissions System30–120 minutes for initial diagnosisP2403 relates to evap system leak detection pump sense circuit/open. Check the fault conditions and vehicle-specific procedure before replacing parts.P2404EVAP System Leak Detection Pump Sense Circuit Range/PerformanceLow priorityEmissions System30–120 minutes for initial diagnosisP2404 relates to evap system leak detection pump sense circuit range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P2405EVAP System Leak Detection Pump Sense Circuit LowLow priorityEmissions System30–120 minutes for initial diagnosisP2405 relates to evap system leak detection pump sense circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P2406EVAP System Leak Detection Pump Sense Circuit HighLow priorityEmissions System30–120 minutes for initial diagnosisP2406 relates to evap system leak detection pump sense circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P2407EVAP System Leak Detection Pump Sense Circuit Intermittent/ErraticLow priorityEmissions System30–120 minutes for initial diagnosisP2407 relates to evap system leak detection pump sense circuit intermittent/erratic. Check the fault conditions and vehicle-specific procedure before replacing parts.P2408Fuel Cap Sensor/Switch CircuitLow priorityFuel System30–120 minutes for initial diagnosisP2408 relates to fuel cap sensor/switch circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.P2409Fuel Cap Sensor/Switch Circuit Range/PerformanceLow priorityFuel System30–120 minutes for initial diagnosisP2409 relates to fuel cap sensor/switch circuit range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P240AEVAP System Leak Detection Pump Heater Control Circuit/OpenLow priorityEmissions System30–120 minutes for initial diagnosisP240A relates to evap system leak detection pump heater control circuit/open. Check the fault conditions and vehicle-specific procedure before replacing parts.P240BEVAP System Leak Detection Pump Heater Control Circuit LowLow priorityEmissions System30–120 minutes for initial diagnosisP240B relates to evap system leak detection pump heater control circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.