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9,253 diagnostic guides

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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.

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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 1–24 of 86

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P0089Fuel Pressure Regulator 1 PerformanceCheck soonFuel System45–120 minutes for initial diagnosisP0089 means Fuel Pressure Regulator 1 Performance. Learn the likely symptoms, causes, safety implications, and a practical diagnostic order.P0093Fuel System Leak Detected — Large LeakUrgentFuel System1–3 hours for initial diagnosisP0093 means Fuel System Leak Detected — Large Leak. Learn the likely symptoms, causes, safety implications, and a practical diagnostic order.P0171System Too Lean Bank 1 - Complete GuideCheck soonFuel System45–120 minutesDiagnose and fix P0171 system too lean code. Understand what causes a lean fuel mixture and how to solve it with our comprehensive guide.P0217Engine Overtemperature ConditionUrgentEngine Problems1–3 hours for initial diagnosisP0217 means Engine Overtemperature Condition. Learn the likely symptoms, causes, safety implications, and a practical diagnostic order.P0340Camshaft Position Sensor Circuit MalfunctionSensors & ElectronicsFix P0340 camshaft sensor code. Learn about cam position sensor function and replacement.P0016Crankshaft/Camshaft Position Correlation Bank 1 Sensor AEngine ProblemsDiagnose P0016 timing correlation code. Learn why the crank and cam signals are out of sync and how to fix it.P0075Intake Valve Control Solenoid Circuit Bank 1Check soonEngine Problems45–120 minutes for initial diagnosisP0075 means Intake Valve Control Solenoid Circuit Bank 1. Learn the likely symptoms, causes, safety implications, and a practical diagnostic order.P0078Exhaust Valve Control Solenoid Circuit Bank 1Check soonEngine Problems45–120 minutes for initial diagnosisP0078 means Exhaust Valve Control Solenoid Circuit Bank 1. Learn the likely symptoms, causes, safety implications, and a practical diagnostic order.P0087Fuel Rail/System Pressure Too Low - Causes & FixesFuel SystemUnderstand P0087 fuel rail pressure too low code - common causes like a failing fuel pump or clogged filter, and how to fix it.P0090Fuel Pressure Regulator 1 Control CircuitCheck soonFuel System45–120 minutes for initial diagnosisP0090 means Fuel Pressure Regulator 1 Control Circuit. Learn the likely symptoms, causes, safety implications, and a practical diagnostic order.P0101MAF Sensor Circuit Range/Performance ProblemCheck soonSensors & Electronics30–90 minutesFix P0101 mass air flow sensor code. Learn how to clean, test, and replace your MAF sensor to restore performance.P0102Mass Air Flow Sensor Circuit Low InputSensors & ElectronicsFix P0102 MAF low input code. Learn why your mass air flow sensor reads low and how to clean, test, or replace it.P0116Coolant Temperature Sensor Range/PerformanceSensors & ElectronicsFix P0116 engine coolant temperature sensor range/performance code - causes, symptoms, and repair steps.P0118Engine Coolant Temperature Sensor High InputSensors & ElectronicsFix the P0118 coolant temperature sensor high-input code, which the ECM reads as an impossibly cold engine.P0190Fuel Rail Pressure Sensor A CircuitCheck soonFuel System45–120 minutes for initial diagnosisP0190 means Fuel Rail Pressure Sensor A Circuit. Learn the likely symptoms, common causes, and a safe diagnostic order before replacing parts.P0200Injector Circuit/OpenCheck soonFuel System45–120 minutes for initial diagnosisP0200 means Injector Circuit/Open. Learn the likely symptoms, common causes, and a safe diagnostic order before replacing parts.P0207Injector Circuit/Open Cylinder 7Check soonFuel System45–120 minutes for initial diagnosisP0207 means Injector Circuit/Open Cylinder 7. Learn the likely symptoms, causes, safety implications, and a practical diagnostic order.P0219Engine Overspeed ConditionUrgentEngine Problems1–3 hours for initial diagnosisP0219 means Engine Overspeed Condition. Learn the likely symptoms, causes, safety implications, and a practical diagnostic order.P0234Turbocharger/Supercharger A Overboost ConditionUrgentEngine Problems1–3 hours for initial diagnosisP0234 means Turbocharger/Supercharger A Overboost Condition. Learn the likely symptoms, common causes, and a safe diagnostic order before replacing parts.P0307Cylinder 7 Misfire DetectedUrgentEngine Problems1–3 hours for initial diagnosisP0307 means Cylinder 7 Misfire Detected. Learn the likely symptoms, common causes, and a safe diagnostic order before replacing parts.P0308Cylinder 8 Misfire DetectedUrgentEngine Problems1–3 hours for initial diagnosisP0308 means Cylinder 8 Misfire Detected. Learn the likely symptoms, common causes, and a safe diagnostic order before replacing parts.P0316Misfire Detected on Startup First 1000 RevolutionsUrgentEngine Problems1–3 hours for initial diagnosisP0316 means Misfire Detected on Startup First 1000 Revolutions. Learn the likely symptoms, common causes, and a safe diagnostic order before replacing parts.P0336Crankshaft Position Sensor Range/PerformanceEngine ProblemsFix P0336 crankshaft position sensor range/performance code - a common cause of stalling and hard starts.P0562System Voltage LowElectrical & Charging SystemFix P0562 system voltage low code. Learn what causes low charging voltage and how to test the battery and alternator.