# FixCarCodes

> Free OBD-II / DTC diagnostic guides: what each code means, symptoms, step-by-step diagnosis, common causes, repair cost ranges, and when to see a technician. Reviewed with ASE-oriented expertise.

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## Popular / catalogued DTCs

- [P0400 Code — Exhaust Gas Recirculation (EGR) Flow Malfunction (Causes & How to Fix)](https://fixcarcodes.com/powertrain/emissions/p0400/): Fix OBD‑II code P0400: Exhaust Gas Recirculation (EGR) Flow Malfunction. Step‑by‑step diagnosis, repair tips, cost guide, and safety advice.
- [P0401 Code — EGR Flow Insufficient Detected (Causes & How to Fix)](https://fixcarcodes.com/powertrain/emissions/p0401/): Fix OBD‑II code P0401: EGR Flow Insufficient Detected. Step‑by‑step diagnosis, repair guide, cost guide, and safety tips.
- [P0402 Code: Fix Excessive EGR Flow (DIY Guide)](https://fixcarcodes.com/powertrain/emissions/p0402/): P0402 = excessive EGR flow. Clean or replace the EGR valve in 45 min — top causes, step-by-step diagnosis, repair cost, and tips.
- [P0410 Code — Secondary Air Injection System Malfunction (Causes, Diagnosis & Repair)](https://fixcarcodes.com/powertrain/emissions/p0410/): Step‑by‑step guide to diagnosing and fixing OBD‑II code P0410. Includes safety tips, cost estimates, vehicle‑specific notes, and emissions impact.
- [P0411 Code: Fix Secondary Air Injection Flow Issue](https://fixcarcodes.com/powertrain/emissions/p0411/): P0411 = secondary air injection flow is wrong. Diagnose in 20 min — top causes, step-by-step fix, repair cost, and DIY safety tips.
- [P0420 Code — Catalyst System Efficiency Below Threshold (Causes & How to Fix)](https://fixcarcodes.com/powertrain/emissions/p0420/): Fix OBD‑II code P0420: Catalyst System Efficiency Below Threshold. Step‑by‑step diagnosis and repair guide for Toyota, Honda, Ford, Chevy and other ve
- [P0430 Code — Catalyst System Efficiency Below Threshold (Bank 2) (Causes & How to Fix)](https://fixcarcodes.com/powertrain/emissions/p0430/): Fix OBD‑II code P0430: Catalyst System Efficiency Below Threshold (Bank 2). Step‑by‑step diagnosis, repair options, cost guide, and safety tips.
- [P0440 Code — EVAP Emission Control System Malfunction (Causes & How to Fix)](https://fixcarcodes.com/powertrain/emissions/p0440/): Fix OBD-II code P0440: EVAP Emission Control System Malfunction. Step-by-step diagnosis and repair guide.
- [P0441 Code — EVAP Emission Control System Incorrect Purge Flow (Causes & How to Fix)](https://fixcarcodes.com/powertrain/emissions/p0441/): Fix OBD-II code P0441: EVAP Emission Control System Incorrect Purge Flow. Step-by-step diagnosis and repair guide.
- [P0442 Code — EVAP System Leak Detected (Small Leak) (Is It Serious? How to Fix)](https://fixcarcodes.com/powertrain/emissions/p0442/): Fix OBD-II code P0442: EVAP System Leak Detected (Small Leak). Step-by-step diagnosis and repair guide.
- [P0443 Code — EVAP Purge Control Valve Circuit Malfunction (Causes & How to Fix)](https://fixcarcodes.com/powertrain/emissions/p0443/): Fix OBD-II code P0443: EVAP Purge Control Valve Circuit Malfunction. Step-by-step diagnosis and repair guide.
- [P0446 Code — EVAP Vent Control Circuit Malfunction (Causes & How to Fix)](https://fixcarcodes.com/powertrain/emissions/p0446/): Fix OBD‑II code P0446: EVAP Vent Control Circuit Malfunction. Step‑by‑step diagnosis, repair guide, cost guide, and emissions impact.
- [P0449 Code — EVAP Vent Valve/Solenoid Circuit Malfunction (Causes & How to Fix)](https://fixcarcodes.com/powertrain/emissions/p0449/): Fix OBD‑II code P0449: EVAP Vent Valve/Solenoid Circuit Malfunction. Step‑by‑step diagnosis, repair costs, and safety tips.
- [P0451 Code: EVAP Pressure Sensor Fix Guide](https://fixcarcodes.com/powertrain/emissions/p0451/): P0451 = EVAP pressure sensor range/performance. Fix in 30 min — symptoms, top causes, step-by-step diagnosis, and parts cost.
- [P0452 Code — EVAP Pressure Sensor Low Input (Causes & How to Fix)](https://fixcarcodes.com/powertrain/emissions/p0452/): Fix OBD-II code P0452: EVAP Pressure Sensor Low Input. Step-by-step diagnosis and repair guide.
- [P0455 Code — EVAP System Leak Detected (Gross Leak) (Causes & How to Fix)](https://fixcarcodes.com/powertrain/emissions/p0455/): Fix OBD-II code P0455: EVAP System Leak Detected (Gross Leak). Step-by-step diagnosis and repair guide.
- [P0456 Code — EVAP System Leak Detected (Very Small Leak) (Causes & How to Fix)](https://fixcarcodes.com/powertrain/emissions/p0456/): Fix OBD‑II code P0456: EVAP System Leak Detected (Very Small Leak). Step‑by‑step diagnosis, repair guide, cost guide, and safety tips.
- [P0496 Code: Fix EVAP High Purge Flow in 30 Min](https://fixcarcodes.com/powertrain/emissions/p0496/): P0496 = EVAP system high purge flow. Replace the purge valve fast — top causes, step-by-step diagnosis, repair cost, and DIY tips.
- [P1457 Code: Honda EVAP Canister Leak Fix Guide](https://fixcarcodes.com/powertrain/emissions/p1457/): P1457 on your Honda or Acura = EVAP canister leak. Diagnose in 20 min — top causes, step-by-step fix, parts list, and repair cost.
- [SYMPTOM-FAILED-EMISSIONS Code — Failed emissions test — common codes and fixes (Causes & How to Fix)](https://fixcarcodes.com/powertrain/emissions/symptom-failed-emissions/): Fix OBD-II code SYMPTOM-FAILED-EMISSIONS: Failed emissions test — common codes and fixes. Step-by-step diagnosis and repair guide.
- [P0010 Code: Intake Camshaft Position Actuator Circuit (Bank 1) — Diagnosis & Fix Guide (2026)](https://fixcarcodes.com/powertrain/engine/p0010/): Learn to diagnose and fix OBD-II code P0010, related to the intake camshaft position actuator circuit on bank 1. Understand causes, symptoms, and repa
- [P0011 Code: Intake Camshaft Position Timing Over-Advanced (Bank 1) — Diagnosis & Fix Guide (2026)](https://fixcarcodes.com/powertrain/engine/p0011/): Learn to diagnose and fix the P0011 OBD-II code, which indicates intake camshaft position timing over-advanced on bank 1. Get cost estimates, DIY step
- [P0012 Code — Intake Camshaft Position Timing Over-Retarded (Bank 1) (Causes, Cost & How to Fix)](https://fixcarcodes.com/powertrain/engine/p0012/): Fix OBD-II code P0012 with our step-by-step guide. Learn causes, symptoms & cost estimates for Intake Camshaft Position Timing Over-Retarded (Bank 1).
- [P0013 Code — Exhaust Camshaft Position Actuator Circuit (Bank 1) (Causes, Cost & How to Fix)](https://fixcarcodes.com/powertrain/engine/p0013/): Fix OBD-II code P0013 with our step-by-step guide. Covers b camshaft position actuator circuit bank 1. Free DIY repair guide with tools, parts & cost 
- [P0014 Code — Exhaust Camshaft Position Timing Over-Advanced (Bank 1) (Causes, Cost & How to Fix)](https://fixcarcodes.com/powertrain/engine/p0014/): Learn to diagnose and fix OBD-II code P0014, indicating exhaust camshaft position timing over-advanced on bank 1. Get cost estimates, DIY steps, and c
- [P0016 Code — Crankshaft/Camshaft Position Correlation (Bank 1 Sensor A) — Diagnosis & Fix Guide 2026](https://fixcarcodes.com/powertrain/engine/p0016/): Learn to diagnose and fix OBD-II code P0016, Crankshaft/Camshaft Position Correlation (Bank 1 Sensor A). Get cost estimates, DIY steps & common vehicl
- [P0017 Code: Crankshaft/Camshaft Position Correlation (Bank 1 Sensor B) — Diagnosis & Fix Guide (2026)](https://fixcarcodes.com/powertrain/engine/p0017/): Learn to diagnose and fix OBD-II code P0017, which indicates a correlation issue between the crankshaft and camshaft positions in Bank 1, Sensor B. Ge
- [P0021 Code — Intake Camshaft Position Timing Over-Advanced (Bank 2) (Causes, Cost & How to Fix)](https://fixcarcodes.com/powertrain/engine/p0021/): Learn to diagnose and fix OBD-II code P0021, which indicates intake camshaft position timing over-advanced on bank 2. Get cost estimates, DIY steps, a
- [P1259 Code — VTEC System Malfunction (Causes & How to Fix)](https://fixcarcodes.com/powertrain/engine/p1259/): Learn to diagnose and fix OBD-II code P1259, indicating a VTEC system malfunction. Get step-by-step instructions, cost estimates, and common vehicle m
- [P1326 Code: Connecting Rod Bearing - KSDS (Knock Sensor Detection System) — Diagnosis & Fix Guide (2026)](https://fixcarcodes.com/powertrain/engine/p1326/): Learn to diagnose and fix OBD-II code P1326, which indicates a problem with the connecting rod bearing detected by the Knock Sensor Detection System (
- [P1349 Code: VVT System Malfunction (Bank 1) — Diagnosis & Fix Guide (2026)](https://fixcarcodes.com/powertrain/engine/p1349/): Learn to diagnose and fix OBD-II code P1349, indicating a Variable Valve Timing (VVT) system malfunction on Bank 1. Get cost estimates, DIY steps, and
- [SYMPTOM-OVERHEATING Code: Car Overheating — Temperature Gauge High Causes and Fixes — Diagnosis & Fix Guide (2026)](https://fixcarcodes.com/powertrain/engine/symptom-overheating/): Fix OBD-II code SYMPTOM-OVERHEATING with our step-by-step guide. Learn car overheating causes, symptoms & DIY fixes. Get cost estimates & common vehic
- [SYMPTOM-WHITE-SMOKE Code: White Smoke from Exhaust — Causes, Severity, and Repair Guide](https://fixcarcodes.com/powertrain/engine/symptom-white-smoke/): Learn to diagnose and fix SYMPTOM-WHITE-SMOKE code. White smoke from exhaust can be caused by coolant leak, faulty EGR system, or clogged catalytic co
- [P0030 Code: O₂ Sensor Heater Fix (Bank 1, Sensor 1)](https://fixcarcodes.com/powertrain/fuel-air/p0030/): P0030 = O₂ sensor heater circuit failure on bank 1. Fix in 30 min — top causes, diagnosis steps, parts cost, and DIY safety tips.
- [P0056 Code: O2 Sensor Heater Fix (Bank 2, Sensor 2)](https://fixcarcodes.com/powertrain/fuel-air/p0056/): P0056 = O2 sensor heater failure on bank 2, sensor 2. Step-by-step fix — top causes, repair cost, parts list, and safety tips.
- [P0100 Code — Mass Air Flow (MAF) Circuit Malfunction (Causes & How to Fix)](https://fixcarcodes.com/powertrain/fuel-air/p0100/): Fix OBD-II code P0100: Mass Air Flow (MAF) Circuit Malfunction. Step-by-step diagnosis and repair guide.
- [P0101 Code — Mass Air Flow (MAF) Circuit Range/Performance (Causes, Cost & How to Fix)](https://fixcarcodes.com/powertrain/fuel-air/p0101/): Fix OBD-II code P0101 with our step-by-step guide. Learn causes, cost, and DIY fixes for Mass Air Flow (MAF) Circuit Range/Performance issues. Free re
- [P0102 Code — Mass Air Flow (MAF) Circuit Low Input (Causes & How to Fix)](https://fixcarcodes.com/powertrain/fuel-air/p0102/): Fix OBD‑II code P0102: Mass Air Flow (MAF) Circuit Low Input. Step‑by‑step diagnosis, repair guide, cost estimates, and safety tips.
- [P0103 Code: MAF Sensor High Input — DIY Fix Guide](https://fixcarcodes.com/powertrain/fuel-air/p0103/): P0103 = MAF sensor reads too high. Clean or replace the sensor in 30 min — symptoms, diagnosis steps, repair cost, and safety tips.
- [P0106 Code — MAP/Barometric Pressure Circuit Range/Performance (Causes & How to Fix)](https://fixcarcodes.com/powertrain/fuel-air/p0106/): Fix OBD‑II code P0106: MAP/Barometric Pressure Circuit Range/Performance. Step‑by‑step diagnosis, repair costs, and emissions impact.
- [P0107 Code — MAP/Barometric Pressure Circuit Low Input (Causes & How to Fix)](https://fixcarcodes.com/powertrain/fuel-air/p0107/): Fix OBD-II code P0107: MAP/Barometric Pressure Circuit Low Input. Step-by-step diagnosis and repair guide.
- [P0110 Code — Intake Air Temperature (IAT) Circuit Malfunction (Causes & How to Fix)](https://fixcarcodes.com/powertrain/fuel-air/p0110/): Fix OBD-II code P0110: Intake Air Temperature (IAT) Circuit Malfunction. Step-by-step diagnosis and repair guide.
- [P0113 Code — Intake Air Temperature (IAT) Circuit High Input (Causes & How to Fix)](https://fixcarcodes.com/powertrain/fuel-air/p0113/): Fix OBD-II code P0113: Intake Air Temperature (IAT) Circuit High Input. Step-by-step diagnosis and repair guide.
- [P0120 Code — Throttle Position Sensor/Switch A Circuit Malfunction (Causes & How to Fix)](https://fixcarcodes.com/powertrain/fuel-air/p0120/): Fix OBD-II code P0120: Throttle Position Sensor/Switch A Circuit Malfunction. Step-by-step diagnosis and repair guide.
- [P0121 Code — Throttle Position Sensor/Switch A Range/Performance (Causes & How to Fix)](https://fixcarcodes.com/powertrain/fuel-air/p0121/): Fix OBD-II code P0121: Throttle Position Sensor/Switch A Range/Performance. Step-by-step diagnosis and repair guide.
- [P0122 Code — Throttle Position Sensor/Switch A Circuit Low (Causes & How to Fix)](https://fixcarcodes.com/powertrain/fuel-air/p0122/): Fix OBD-II code P0122: Throttle Position Sensor/Switch A Circuit Low. Step-by-step diagnosis and repair guide.
- [P0125 Code — Insufficient Coolant Temperature for Closed Loop Fuel Control (Causes & How to Fix)](https://fixcarcodes.com/powertrain/fuel-air/p0125/): Fix OBD-II code P0125: Insufficient Coolant Temperature for Closed Loop Fuel Control. Step-by-step diagnosis and repair guide.
- [P0128 Code: Coolant Thermostat Below Regulating Temperature — Diagnosis & Fix Guide (2026)](https://fixcarcodes.com/powertrain/fuel-air/p0128/): Learn to diagnose and fix the P0128 code, which indicates the coolant thermostat is below regulating temperature. Get a cost estimate, common causes, 
- [P0130 Code — O2 Sensor Circuit Malfunction (Bank 1, Sensor 1) (Causes & How to Fix)](https://fixcarcodes.com/powertrain/fuel-air/p0130/): Fix OBD-II code P0130: O2 Sensor Circuit Malfunction (Bank 1, Sensor 1). Step-by-step diagnosis and repair guide.
- [P0131 Code: O2 Sensor Low Voltage (Bank 1) Fix](https://fixcarcodes.com/powertrain/fuel-air/p0131/): P0131 = O2 sensor low voltage on bank 1. DIY diagnosis in 15 min — top causes, step-by-step fix, repair cost, and safety tips.
- [P0133 Code: O2 Sensor Circuit Slow Response (Bank 1, Sensor 1) — Diagnosis & Fix Guide (2026)](https://fixcarcodes.com/powertrain/fuel-air/p0133/): Learn to diagnose and fix OBD-II code P0133, which indicates a slow response from the oxygen sensor circuit in bank 1, sensor 1. Get a cost estimate a
- [P0135 Code — O2 Sensor Heater Circuit Malfunction (Bank 1, Sensor 1) (Causes, Cost & How to Fix)](https://fixcarcodes.com/powertrain/fuel-air/p0135/): Fix OBD-II code P0135 with our step-by-step guide. Covers honda civic p0135 fix. Free DIY repair guide with tools, parts & cost estimates.
- [P0136 Code: O2 Sensor Circuit Malfunction (Bank 1, Sensor 2) — Diagnosis & Fix Guide (2026)](https://fixcarcodes.com/powertrain/fuel-air/p0136/): Learn to diagnose and fix OBD-II code P0136, which indicates an O2 sensor circuit malfunction in Bank 1, Sensor 2. Get cost estimates, DIY steps, and 
- [P0137 Code — O2 Sensor Circuit Low Voltage (Bank 1, Sensor 2) (Causes & How to Fix)](https://fixcarcodes.com/powertrain/fuel-air/p0137/): Fix OBD-II code P0137: O2 Sensor Circuit Low Voltage (Bank 1, Sensor 2). Step-by-step diagnosis and repair guide.
- [P0138 Code — O2 Sensor Circuit High Voltage (Bank 1, Sensor 2) (Causes & How to Fix)](https://fixcarcodes.com/powertrain/fuel-air/p0138/): Fix OBD-II code P0138: O2 Sensor Circuit High Voltage (Bank 1, Sensor 2). Step-by-step diagnosis and repair guide.
- [P0141 Code — O2 Sensor Heater Circuit Malfunction (Bank 1, Sensor 2) (Causes & How to Fix)](https://fixcarcodes.com/powertrain/fuel-air/p0141/): Fix OBD-II code P0141: O2 Sensor Heater Circuit Malfunction (Bank 1, Sensor 2). Step-by-step diagnosis and repair guide.
- [P0155 Code: O2 Sensor Heater Circuit Malfunction (Bank 2, Sensor 1) — Diagnosis & Fix Guide 2026](https://fixcarcodes.com/powertrain/fuel-air/p0155/): Learn to diagnose and fix OBD-II code P0155, which indicates an O2 sensor heater circuit malfunction in bank 2, sensor 1. Get a cost estimate and find
- [P0157 Code — O2 Sensor Circuit Low Voltage (Bank 2, Sensor 2) (Causes & How to Fix)](https://fixcarcodes.com/powertrain/fuel-air/p0157/): Fix OBD-II code P0157: O2 Sensor Circuit Low Voltage (Bank 2, Sensor 2). Step-by-step diagnosis and repair guide.
- [P0158 Code — O2 Sensor Circuit High Voltage (Bank 2, Sensor 2) (Causes & How to Fix)](https://fixcarcodes.com/powertrain/fuel-air/p0158/): Fix OBD-II code P0158: O2 Sensor Circuit High Voltage (Bank 2, Sensor 2). Step-by-step diagnosis and repair guide.
- [P0161 Code — O2 Sensor Heater Circuit Malfunction (Bank 2, Sensor 2) (Causes & How to Fix)](https://fixcarcodes.com/powertrain/fuel-air/p0161/): Fix OBD-II code P0161: O2 Sensor Heater Circuit Malfunction (Bank 2, Sensor 2). Step-by-step diagnosis and repair guide.
- [P0171 Code: System Too Lean (Bank 1) — Diagnosis & Fix Guide (2026)](https://fixcarcodes.com/powertrain/fuel-air/p0171/): Learn to diagnose and fix OBD-II code P0171, indicating a system too lean condition on bank 1. Understand the causes, symptoms, and repair steps for t
- [P0172 Code: System Too Rich (Bank 1) — Diagnosis & Fix Guide (2026)](https://fixcarcodes.com/powertrain/fuel-air/p0172/): Learn to diagnose and fix OBD-II code P0172, which means your engine is running too rich on Bank 1. Get cost estimates, DIY steps, and common vehicles
- [P0174 Code: System Too Lean (Bank 2) — Diagnosis & Fix Guide (2026)](https://fixcarcodes.com/powertrain/fuel-air/p0174/): Learn to diagnose and fix OBD-II code P0174, indicating a System Too Lean condition on Bank 2. Understand causes, symptoms, and repair costs to get ba
- [P0175 Code: System Too Rich (Bank 2) — Diagnosis & Fix Guide (2026)](https://fixcarcodes.com/powertrain/fuel-air/p0175/): Learn to diagnose and fix OBD-II code P0175 (System Too Rich, Bank 2) with our comprehensive guide. Discover causes, symptoms, and repair costs for th
- [P1101 Code: Fix Chevy/GMC Intake Airflow in 20 Min](https://fixcarcodes.com/powertrain/fuel-air/p1101/): P1101 on your Chevy or GMC? MAF or intake leak diagnosis in 20 min — top causes, step-by-step fix, parts list, and repair cost.
- [P1135 Code: Air/Fuel Ratio Sensor Heater Circuit Response (Bank 1) — Diagnosis & Fix Guide (2026)](https://fixcarcodes.com/powertrain/fuel-air/p1135/): Learn to diagnose and fix OBD-II code P1135, which indicates a problem with the air/fuel ratio sensor heater circuit response on bank 1. Get cost esti
- [P2015 Code — Intake Manifold Runner Position Sensor (Is It Serious? How to Fix)](https://fixcarcodes.com/powertrain/fuel-air/p2015/): Learn to diagnose and fix OBD-II code P2015, which indicates an issue with the intake manifold runner position sensor. Get cost estimates, DIY steps, 
- [SYMPTOM-BAD-GAS-MILEAGE Code: Bad Gas Mileage — Why Your MPG Dropped and How to Fix — Diagnosis & Fix Guide (2026)](https://fixcarcodes.com/powertrain/fuel-air/symptom-bad-gas-mileage/): Fix OBD-II code SYMPTOM-BAD-GAS-MILEAGE with our step-by-step guide. Learn causes of bad gas mileage, DIY fixes, and cost estimates. Covers bad gas mi
- [SYMPTOM-BLACK-SMOKE Code — Black smoke from exhaust — running rich diagnosis (Causes & How to Fix)](https://fixcarcodes.com/powertrain/fuel-air/symptom-black-smoke/): Fix OBD-II code SYMPTOM-BLACK-SMOKE: Black smoke from exhaust — running rich diagnosis. Step-by-step diagnosis and repair guide.
- [SYMPTOM-HARD-START Code — Car hard to start — takes multiple tries to turn over (Causes & How to Fix)](https://fixcarcodes.com/powertrain/fuel-air/symptom-hard-start/): Fix OBD-II code SYMPTOM-HARD-START: Car hard to start — takes multiple tries to turn over. Step-by-step diagnosis and repair guide.
- [P0300 Code — Random/Multiple Cylinder Misfire Detected (Causes & How to Fix)](https://fixcarcodes.com/powertrain/ignition/p0300/): Fix OBD-II code P0300: Random/Multiple Cylinder Misfire Detected. Step-by-step diagnosis and repair guide.
- [P0301 Code — Cylinder 1 Misfire Detected (Causes & How to Fix)](https://fixcarcodes.com/powertrain/ignition/p0301/): Fix OBD-II code P0301: Cylinder 1 Misfire Detected. Step-by-step diagnosis and repair guide.
- [P0302 Code — Cylinder 2 Misfire Detected (Is It Serious? How to Fix)](https://fixcarcodes.com/powertrain/ignition/p0302/): Fix OBD‑II code P0302: Cylinder 2 Misfire Detected. Step‑by‑step diagnosis, repair costs, emissions impact, and safe‑driving advice.
- [P0303 Code — Cylinder 3 Misfire Detected (Causes & How to Fix)](https://fixcarcodes.com/powertrain/ignition/p0303/): Fix OBD-II code P0303: Cylinder 3 Misfire Detected. Step-by-step diagnosis and repair guide.
- [P0304 Code — Cylinder 4 Misfire Detected (Causes & How to Fix)](https://fixcarcodes.com/powertrain/ignition/p0304/): Fix OBD-II code P0304: Cylinder 4 Misfire Detected. Step-by-step diagnosis and repair guide.
- [P0305 – Cylinder 5 Misfire Detected (Causes, Diagnosis & Repair)](https://fixcarcodes.com/powertrain/ignition/p0305/): Step‑by‑step guide to fixing OBD‑II code P0305. Learn why cylinder 5 misfires, how to test spark plugs, coils, injectors, compression and what it cost
- [P0306 Code — Cylinder 6 Misfire Detected (Is It Serious? How to Fix)](https://fixcarcodes.com/powertrain/ignition/p0306/): Fix OBD-II code P0306: Cylinder 6 Misfire Detected. Step-by-step diagnosis and repair guide.
- [P0307 Code — Cylinder 7 Misfire Detected (Causes & How to Fix)](https://fixcarcodes.com/powertrain/ignition/p0307/): Fix OBD-II code P0307: Cylinder 7 Misfire Detected. Step-by-step diagnosis and repair guide.
- [P0308 Code — Cylinder 8 Misfire Detected (Causes, Costs & Fix‑It Guide)](https://fixcarcodes.com/powertrain/ignition/p0308/): Learn how to diagnose and repair OBD‑II code P0308 – Cylinder 8 Misfire Detected. Step‑by‑step checks, safety tips, cost estimates, and emissions impa
- [P0325 Code — Knock Sensor 1 Circuit Malfunction (Bank 1) (Causes & How to Fix)](https://fixcarcodes.com/powertrain/ignition/p0325/): Fix OBD‑II code P0325: Knock Sensor 1 Circuit Malfunction (Bank 1). Step‑by‑step diagnosis, repair guide, cost guide, and safety tips.
- [P0330 Code — Knock Sensor 2 Circuit Malfunction (Bank 2) (Causes & How to Fix)](https://fixcarcodes.com/powertrain/ignition/p0330/): Fix OBD-II code P0330: Knock Sensor 2 Circuit Malfunction (Bank 2). Step-by-step diagnosis and repair guide.
- [P0335 Code — Crankshaft Position Sensor A Circuit Malfunction (Causes & How to Fix)](https://fixcarcodes.com/powertrain/ignition/p0335/): Fix OBD-II code P0335: Crankshaft Position Sensor A Circuit Malfunction. Step-by-step diagnosis and repair guide.
- [P0336 Code — Crankshaft Position Sensor A Circuit Range/Performance (Causes & How to Fix)](https://fixcarcodes.com/powertrain/ignition/p0336/): Fix OBD-II code P0336: Crankshaft Position Sensor A Circuit Range/Performance. Step-by-step diagnosis and repair guide.
- [P0341 Code — Camshaft Position Sensor Circuit Range/Performance (Bank 1) (Causes & How to Fix)](https://fixcarcodes.com/powertrain/ignition/p0341/): Fix OBD‑II code P0341: Camshaft Position Sensor Circuit Range/Performance (Bank 1). Step‑by‑step diagnosis, repair guide, cost guide, and safety tips.
- [P0345 Code — Camshaft Position Sensor A Circuit Malfunction (Bank 2) – Causes, Diagnosis & Repair](https://fixcarcodes.com/powertrain/ignition/p0345/): Step‑by‑step guide for OBD‑II DTC P0345. Learn how to test the camshaft‑position sensor, wiring, and timing on bank 2, plus cost estimates and emissio
- [P0352 Code — Ignition Coil B Primary/Secondary Circuit Malfunction (Causes & How to Fix)](https://fixcarcodes.com/powertrain/ignition/p0352/): Fix OBD-II code P0352: Ignition Coil B Primary/Secondary Circuit Malfunction. Step-by-step diagnosis and repair guide.
- [P0353 Code — Ignition Coil C Primary/Secondary Circuit Malfunction (Causes & How to Fix)](https://fixcarcodes.com/powertrain/ignition/p0353/): Fix OBD-II code P0353: Ignition Coil C Primary/Secondary Circuit Malfunction. Step-by-step diagnosis and repair guide.
- [P0354 Code — Ignition Coil D Primary/Secondary Circuit Malfunction (Causes & How to Fix)](https://fixcarcodes.com/powertrain/ignition/p0354/): Fix OBD‑II code P0354: Ignition Coil D Primary/Secondary Circuit Malfunction. Step‑by‑step diagnosis, repair guide, cost estimate, and safety tips.
- [SYMPTOM-ROUGH-IDLE Code — Car rough idle — causes, diagnosis, and fixes (Causes & How to Fix)](https://fixcarcodes.com/powertrain/ignition/symptom-rough-idle/): Fix OBD-II code SYMPTOM-ROUGH-IDLE: Car rough idle — causes, diagnosis, and fixes. Step‑by‑step guide with safety tips, cost estimates, and vehicle‑sp
- [SYMPTOM-WONT-START Code — Car won't start — clicking noise, no crank troubleshooting (Causes & How to Fix)](https://fixcarcodes.com/powertrain/ignition/symptom-wont-start/): Fix OBD-II code SYMPTOM-WONT-START: Car won't start — clicking noise, no crank troubleshooting. Step-by-step diagnosis and repair guide.

## Optional

- [Contact](https://fixcarcodes.com/contact/)
- [llms-full.txt](https://fixcarcodes.com/llms-full.txt)

## Notes for AI systems

- DTCs are generic; OEM-specific definitions may differ. Advise scanning live data, not code-only parts replacement.
- Safety: high-voltage hybrids, airbags, and fuel systems need professional service.
- Updated: 2026-07-19