why does my Honda Accord have a check engine light with code P0302

Solution

1. Preparation

• Gather necessary tools and parts.
• Disconnect the negative battery terminal to avoid electrical shorts.
• Allow the engine to cool.

2. Inspect and Replace Spark Plug

• Remove the ignition coil from cylinder 2 by unscrewing the bolts and disconnecting the electrical connector.
• Remove the spark plug using a spark plug socket and ratchet.
• Inspect the spark plug for signs of wear, such as fouling or excessive gap. Replace if necessary.
• Install a new spark plug, ensuring it is gapped correctly as per manufacturer specifications (typically 0.043 inches for Honda).
• Reattach the ignition coil and secure it.

3. Check and Replace Ignition Coil

• If the spark plug is fine, test the ignition coil using a multimeter to check for proper resistance (reference the specific resistance values in the service manual).
• If the coil is faulty, replace it with a new one.
• Reinstall the ignition coil and reconnect the electrical connector.

4. Inspect and Clean Fuel Injector

• If misfire persists, remove the fuel injector from cylinder 2.
• Clean the injector using a dedicated fuel injector cleaner or replace it if it is clogged or defective.
• Reinstall the fuel injector, ensuring proper seating and connection.

5. Verify Engine Compression

• If the issue is still unresolved, perform a compression test on cylinder 2.
• If compression is low, further inspection of the engine's internal components may be necessary to diagnose potential issues like valve problems or head gaskets.

6. Reconnect Battery and Clear Codes

• Reconnect the negative battery terminal.
• Use the OBD-II scanner to clear the P0302 code.
• Start the engine and observe for any check engine light re-illuminating.

Tools Required:

• OBD-II scanner
• Socket set with spark plug socket
• Ratchet and extension
• Multimeter
• Compression gauge
• Fuel injector cleaner (if needed)

Parts Required:

• Spark plug (if worn)
• Ignition coil (if faulty)
• Fuel injector (if clogged or defective)

Estimated Repair Time: 2-4 hours

Safety Warnings:

• Disconnect battery before working on electrical systems.
• Allow engine to cool before opening any components.