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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 145–168 of 975

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P023FFuel Pump Secondary Circuit/OpenCheck soonFuel System30–120 minutes for initial diagnosisP023F relates to fuel pump secondary circuit/open. Check the fault conditions and vehicle-specific procedure before replacing parts.P0251Injection Pump Fuel Metering Control A (Cam/Rotor/Injector)Check soonFuel System30–120 minutes for initial diagnosisP0251 relates to injection pump fuel metering control a (cam/rotor/injector). Check the fault conditions and vehicle-specific procedure before replacing parts.P0252Injection Pump Fuel Metering Control A Range/Performance (Cam/Rotor/Injector)Check soonFuel System30–120 minutes for initial diagnosisP0252 relates to injection pump fuel metering control a range/performance (cam/rotor/injector). Check the fault conditions and vehicle-specific procedure before replacing parts.P0253Injection Pump Fuel Metering Control A Low (Cam/Rotor/Injector)Check soonFuel System30–120 minutes for initial diagnosisP0253 relates to injection pump fuel metering control a low (cam/rotor/injector). Check the fault conditions and vehicle-specific procedure before replacing parts.P0254Injection Pump Fuel Metering Control A High (Cam/Rotor/Injector)Check soonFuel System30–120 minutes for initial diagnosisP0254 relates to injection pump fuel metering control a high (cam/rotor/injector). Check the fault conditions and vehicle-specific procedure before replacing parts.P0255Injection Pump Fuel Metering Control A Intermittent (Cam/Rotor/Injector)Check soonFuel System30–120 minutes for initial diagnosisP0255 relates to injection pump fuel metering control a intermittent (cam/rotor/injector). Check the fault conditions and vehicle-specific procedure before replacing parts.P0256Injection Pump Fuel Metering Control B (Cam/Rotor/Injector)Check soonFuel System30–120 minutes for initial diagnosisP0256 relates to injection pump fuel metering control b (cam/rotor/injector). Check the fault conditions and vehicle-specific procedure before replacing parts.P0257Injection Pump Fuel Metering Control B Range/Performance (Cam/Rotor/Injector)Check soonFuel System30–120 minutes for initial diagnosisP0257 relates to injection pump fuel metering control b range/performance (cam/rotor/injector). Check the fault conditions and vehicle-specific procedure before replacing parts.P0258Injection Pump Fuel Metering Control B Low (Cam/Rotor/Injector)Check soonFuel System30–120 minutes for initial diagnosisP0258 relates to injection pump fuel metering control b low (cam/rotor/injector). Check the fault conditions and vehicle-specific procedure before replacing parts.P0259Injection Pump Fuel Metering Control B High (Cam/Rotor/Injector)Check soonFuel System30–120 minutes for initial diagnosisP0259 relates to injection pump fuel metering control b high (cam/rotor/injector). Check the fault conditions and vehicle-specific procedure before replacing parts.P025AFuel Pump Module A Control Circuit/OpenCheck soonFuel System30–120 minutes for initial diagnosisP025A relates to fuel pump module a control circuit/open. Check the fault conditions and vehicle-specific procedure before replacing parts.P025BFuel Pump Module A Control Circuit Range/PerformanceCheck soonFuel System30–120 minutes for initial diagnosisP025B relates to fuel pump module a control circuit range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P025CFuel Pump Module A Control Circuit LowCheck soonFuel System30–120 minutes for initial diagnosisP025C relates to fuel pump module a control circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P025DFuel Pump Module A Control Circuit HighCheck soonFuel System30–120 minutes for initial diagnosisP025D relates to fuel pump module a control circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P0260Injection Pump Fuel Metering Control B Intermittent (Cam/Rotor/Injector)Check soonFuel System30–120 minutes for initial diagnosisP0260 relates to injection pump fuel metering control b intermittent (cam/rotor/injector). Check the fault conditions and vehicle-specific procedure before replacing parts.P0261Cylinder 1 Injector A Circuit LowCheck soonFuel System30–120 minutes for initial diagnosisP0261 relates to cylinder 1 injector a circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P0262Cylinder 1 Injector A Circuit HighCheck soonFuel System30–120 minutes for initial diagnosisP0262 relates to cylinder 1 injector a circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P0264Cylinder 2 Injector A Circuit LowCheck soonFuel System30–120 minutes for initial diagnosisP0264 relates to cylinder 2 injector a circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P0265Cylinder 2 Injector A Circuit HighCheck soonFuel System30–120 minutes for initial diagnosisP0265 relates to cylinder 2 injector a circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P0267Cylinder 3 Injector A Circuit LowCheck soonFuel System30–120 minutes for initial diagnosisP0267 relates to cylinder 3 injector a circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P0268Cylinder 3 Injector A Circuit HighCheck soonFuel System30–120 minutes for initial diagnosisP0268 relates to cylinder 3 injector a circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P026BInjection Timing PerformanceCheck soonFuel System30–120 minutes for initial diagnosisP026B relates to injection timing performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P026CFuel Injection Quantity A Lower Than ExpectedCheck soonFuel System30–120 minutes for initial diagnosisP026C relates to fuel injection quantity a lower than expected. Check the fault conditions and vehicle-specific procedure before replacing parts.P026DFuel Injection Quantity A Higher Than ExpectedCheck soonFuel System30–120 minutes for initial diagnosisP026D relates to fuel injection quantity a higher than expected. Check the fault conditions and vehicle-specific procedure before replacing parts.