P0302 – OBD-II DTC

OBD-II DTC P0302 – Cylinder 1 Misfire Detected

DTC P0302 meaning

DTC P0302 indicates that the Engine Control Module (ECM) has detected a misfire in cylinder 2 of the engine. A misfire occurs when the air-fuel mixture in the cylinder fails to ignite properly, leading to a loss of power and increased emissions. This code is part of the On-Board Diagnostics II (OBD-II) system, which monitors the performance of the engine and its components.

DTC P0302 symptoms

Common symptoms associated with DTC P0302 include:

• Rough engine idle
• Decreased engine performance
• Increased fuel consumption
• Engine stalling
• Check Engine Light (CEL) illuminated

DTC P0302 causes

Several factors can lead to the triggering of DTC P0302, including:

• Faulty spark plug or spark plug wire
• Defective fuel injector
• Vacuum leaks
• Low compression in the cylinder
• Faulty ignition coil
• Engine timing issues

DTC P0302 seriousness

DTC P0302 is considered a serious issue as it can lead to further engine damage if not addressed. Continuous misfires can cause:

• Increased wear on engine components
• Damage to the catalytic converter
• Reduced fuel efficiency
• Potential engine overheating

How to diagnose DTC P0302

To diagnose DTC P0302, follow these steps:

1. Use an OBD-II scanner to confirm the code and check for any additional codes.
2. Inspect the spark plug and ignition coil for signs of wear or damage.
3. Check the fuel injector operation and ensure it is delivering fuel properly.
4. Examine vacuum lines for leaks that could affect air-fuel mixture.
5. Perform a compression test on cylinder 2 to check for mechanical issues.

How to fix DTC P0302 step-by-step instructions

To fix DTC P0302, follow these steps:

1. Replace the faulty spark plug or spark plug wire if damaged.
2. Replace or clean the fuel injector if it is malfunctioning.
3. Repair any vacuum leaks found during inspection.
4. Replace the ignition coil if it is not functioning correctly.
5. Address any timing issues by checking the timing belt or chain.
6. Clear the DTC using an OBD-II scanner and test drive the vehicle to ensure the issue is resolved.

How to erase DTC P0302

To erase DTC P0302, follow these steps:

1. Connect an OBD-II scanner to the vehicle’s diagnostic port.
2. Turn on the ignition without starting the engine.
3. Navigate to the “Erase Codes” or “Clear Codes” option on the scanner.
4. Confirm the action to clear the DTC from the ECM.
5. Disconnect the scanner and start the engine to verify that the code does not return.

Recommended tools for OBD-II diagnostics

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