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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.

“misfire”Urgent Clear all

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Engine1049 Emissions515 Fuel1016 Sensors & Electronics2110 Transmission866 Electrical & Charging1797 Body & Restraints193 Chassis & Brakes479 Network & Communication1228

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Severity

All severities9253 Low priority305 Check soon8256 Urgent621

Code family

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 1–8 of 8

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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.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.P0303Cylinder 3 Misfire Detected - Diagnosis GuideUrgentEngine Problems30–75 minutesFix P0303 cylinder 3 misfire code. Learn the common causes and proven solutions for cylinder 3 misfiring.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.