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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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Diagnostic codes

Showing 1–24 of 53

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P050DCold Start Rough IdleCheck soonSensors & Electronics30–120 minutes for initial diagnosisP050D relates to cold start rough idle. Check the fault conditions and vehicle-specific procedure before replacing parts.P0130O2 Sensor Circuit Malfunction Bank 1 Sensor 1Sensors & ElectronicsFix P0130 oxygen sensor code. Learn about O2 sensor locations, testing procedures, and replacement tips for Bank 1 Sensor 1.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.P0172System Too Rich Bank 1 - Causes & SolutionsFuel SystemDiagnose P0172 rich fuel mixture code. Learn what causes excess fuel in the air-fuel mixture and how to fix it.P0304Cylinder 4 Misfire Detected - Causes & FixesUrgentEngine Problems30–75 minutesLearn what P0304 means, why cylinder 4 is misfiring, and how to fix it. Complete guide with symptoms, causes, and step-by-step solutions.P0011Camshaft Position Timing Over-Advanced Bank 1Engine ProblemsFix P0011 variable valve timing code. Learn what causes over-advanced cam timing on Bank 1 and how to repair it.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.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.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.P0106MAP Sensor Range/Performance ProblemSensors & ElectronicsLearn what triggers P0106 MAP sensor range/performance code and how to fix an implausible manifold pressure reading.P0131O2 Sensor Low Voltage Bank 1 Sensor 1Sensors & ElectronicsDiagnose P0131 oxygen sensor low voltage code. Learn why the upstream O2 sensor is reading low and how to fix it.P0132O2 Sensor Circuit High Voltage Bank 1 Sensor 1Sensors & ElectronicsDiagnose the P0132 high-voltage oxygen sensor code on Bank 1 Sensor 1, including a rich-condition check and sensor testing.P0133O2 Sensor Slow Response Bank 1 Sensor 1Sensors & ElectronicsFix P0133 slow responding oxygen sensor. Learn why the O2 sensor is responding slowly and repair options.P0174System Too Lean Bank 2 - Causes & SolutionsFuel SystemFix P0174 lean condition on Bank 2. Often appears with P0171. Learn the common causes and effective repair strategies.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.P0201Injector Circuit Malfunction Cylinder 1Fuel SystemDiagnose P0201 fuel injector circuit fault on cylinder 1 - wiring, driver, and injector causes plus fixes.P0300Random/Multiple Cylinder Misfire DetectedUrgentEngine Problems30–90 minutesDiagnose P0300 random misfire code. Learn why multiple cylinders are misfiring and the systematic approach to finding the cause.P0301Cylinder 1 Misfire Detected - Diagnosis GuideUrgentEngine Problems30–75 minutesComplete guide to P0301 cylinder 1 misfire. Find out what's causing the misfire and how to fix it step by step.P0302Cylinder 2 Misfire Detected - Causes & FixesUrgentEngine Problems30–75 minutesComplete guide to P0302 cylinder 2 misfire. Diagnose and fix the misfire with our step-by-step troubleshooting guide.P0305Cylinder 5 Misfire Detected - Causes & FixesEngine ProblemsLearn what P0305 means, why cylinder 5 is misfiring, and how to diagnose and fix it with a clear step-by-step approach.P0306Cylinder 6 Misfire Detected - Diagnosis GuideEngine ProblemsComplete guide to the P0306 cylinder 6 misfire code, including symptoms, common causes, and step-by-step fixes.P0400Exhaust Gas Recirculation Flow MalfunctionLow priorityEmissions System30–90 minutes for initial diagnosisP0400 means Exhaust Gas Recirculation Flow Malfunction. Learn the likely symptoms, common causes, and a safe diagnostic order before replacing parts.P0401EGR Insufficient Flow DetectedEmissions SystemFix P0401 EGR flow code. Learn about the exhaust gas recirculation system and how to restore proper flow.