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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.

Check soon P · Powertrain 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 3433–3456 of 6682

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P2171Exhaust Pressure Regulator Vent Solenoid Control Circuit HighCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2171 relates to exhaust pressure regulator vent solenoid control circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P2172Throttle Actuator Control System - Sudden High Air Flow DetectedCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2172 relates to throttle actuator control system - sudden high air flow detected. Check the fault conditions and vehicle-specific procedure before replacing parts.P2173Throttle Actuator Control System - High Air Flow DetectedCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2173 relates to throttle actuator control system - high air flow detected. Check the fault conditions and vehicle-specific procedure before replacing parts.P2174Throttle Actuator Control System - Sudden Low Air Flow DetectedCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2174 relates to throttle actuator control system - sudden low air flow detected. Check the fault conditions and vehicle-specific procedure before replacing parts.P2175Throttle Actuator Control System - Low Air Flow DetectedCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2175 relates to throttle actuator control system - low air flow detected. Check the fault conditions and vehicle-specific procedure before replacing parts.P2176Throttle Actuator A Control System - Idle Position Not LearnedCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2176 relates to throttle actuator a control system - idle position not learned. Check the fault conditions and vehicle-specific procedure before replacing parts.P2177System Too Lean Off Idle Bank 1Check soonSensors & Electronics30–120 minutes for initial diagnosisP2177 relates to system too lean off idle bank 1. Check the fault conditions and vehicle-specific procedure before replacing parts.P2178System Too Rich Off Idle Bank 1Check soonSensors & Electronics30–120 minutes for initial diagnosisP2178 relates to system too rich off idle bank 1. Check the fault conditions and vehicle-specific procedure before replacing parts.P2179System Too Lean Off Idle Bank 2Check soonSensors & Electronics30–120 minutes for initial diagnosisP2179 relates to system too lean off idle bank 2. Check the fault conditions and vehicle-specific procedure before replacing parts.P217AFuel Injector Group G Supply Voltage Circuit/OpenCheck soonFuel System30–120 minutes for initial diagnosisP217A relates to fuel injector group g supply voltage circuit/open. Check the fault conditions and vehicle-specific procedure before replacing parts.P217BFuel Injector Group G Supply Voltage Circuit LowCheck soonFuel System30–120 minutes for initial diagnosisP217B relates to fuel injector group g supply voltage circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P217CFuel Injector Group G Supply Voltage Circuit HighCheck soonFuel System30–120 minutes for initial diagnosisP217C relates to fuel injector group g supply voltage circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P217DFuel Injector Group H Supply Voltage Circuit/OpenCheck soonFuel System30–120 minutes for initial diagnosisP217D relates to fuel injector group h supply voltage circuit/open. Check the fault conditions and vehicle-specific procedure before replacing parts.P217EFuel Injector Group H Supply Voltage Circuit LowCheck soonFuel System30–120 minutes for initial diagnosisP217E relates to fuel injector group h supply voltage circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P217FFuel Injector Group H Supply Voltage Circuit HighCheck soonFuel System30–120 minutes for initial diagnosisP217F relates to fuel injector group h supply voltage circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P2180System Too Rich Off Idle Bank 2Check soonSensors & Electronics30–120 minutes for initial diagnosisP2180 relates to system too rich off idle bank 2. Check the fault conditions and vehicle-specific procedure before replacing parts.P2181Cooling System PerformanceCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2181 relates to cooling system performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P2182Engine Coolant Temperature Sensor 2 CircuitCheck soonEngine Problems30–120 minutes for initial diagnosisP2182 relates to engine coolant temperature sensor 2 circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.P2183Engine Coolant Temperature Sensor 2 Circuit Range/PerformanceCheck soonEngine Problems30–120 minutes for initial diagnosisP2183 relates to engine coolant temperature sensor 2 circuit range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P2184Engine Coolant Temperature Sensor 2 Circuit LowCheck soonEngine Problems30–120 minutes for initial diagnosisP2184 relates to engine coolant temperature sensor 2 circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P2185Engine Coolant Temperature Sensor 2 Circuit HighCheck soonEngine Problems30–120 minutes for initial diagnosisP2185 relates to engine coolant temperature sensor 2 circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P2186Engine Coolant Temperature Sensor 2 Circuit Intermittent/ErraticCheck soonEngine Problems30–120 minutes for initial diagnosisP2186 relates to engine coolant temperature sensor 2 circuit intermittent/erratic. Check the fault conditions and vehicle-specific procedure before replacing parts.P2187System Too Lean at Idle Bank 1Check soonSensors & Electronics30–120 minutes for initial diagnosisP2187 relates to system too lean at idle bank 1. Check the fault conditions and vehicle-specific procedure before replacing parts.P2188System Too Rich at Idle Bank 1Check soonSensors & Electronics30–120 minutes for initial diagnosisP2188 relates to system too rich at idle bank 1. Check the fault conditions and vehicle-specific procedure before replacing parts.