how to diagnose P0302 code on my Honda Accord 9th Generation (2013-2017)

Solution

1. Preparation

• Gather necessary tools and parts.
• Ensure the vehicle is parked on a level surface and the engine is cool.
• Disconnect the negative terminal of the battery.

2. Inspect and Replace Spark Plug

• Sub-steps:
  1. Remove the engine cover if applicable.
  2. Locate the cylinder 2 spark plug (usually the second from the timing belt).
  3. Use a spark plug socket to remove the spark plug.
  4. Inspect the spark plug for wear, carbon deposits, or damage.
  5. Replace with a new spark plug, ensuring the correct gap (0.043 inches for most Honda models).
  6. Torque the new spark plug to the manufacturer’s specification (typically 13 lb-ft).

3. Check and Replace Ignition Coil

• Sub-steps:
  1. Disconnect the ignition coil connector for cylinder 2.
  2. Remove the mounting bolt and take out the ignition coil.
  3. Inspect the coil for any visible damage or corrosion.
  4. If swapping did not resolve the misfire, install a new ignition coil.
  5. Reinstall the ignition coil and reconnect the connector.

4. Inspect and Test Fuel Injector

• Sub-steps:
  1. Locate the fuel injector for cylinder 2.
  2. Disconnect the fuel injector connector.
  3. Use a multimeter to check the injector's resistance (should be within specs, often around 12-16 ohms).
  4. If the injector is faulty, replace it with a new one.
  5. Reconnect the fuel injector connector.

5. Perform Compression Test

• Sub-steps:
  1. Remove the spark plug for cylinder 2.
  2. Install the compression gauge into the spark plug hole.
  3. Crank the engine several times and record the reading.
  4. Compare the reading to other cylinders and manufacturer specifications.
  5. If compression is low, further investigation of the cylinder head or piston may be necessary.

6. Check for Vacuum Leaks

• Sub-steps:
  1. Inspect hoses and gaskets around the intake manifold for cracks or disconnections.
  2. Use a smoke tester to identify any vacuum leaks.
  3. Repair or replace any damaged components found during inspection.

Tools Required:

• OBD-II scanner
• Spark plug socket
• Torque wrench
• Multimeter
• Compression gauge
• Smoke tester (optional)

Parts Required:

• Spark plug (for cylinder 2)
• Ignition coil (if needed)
• Fuel injector (if needed)

Estimated Repair Time: 2-4 hours

Safety Warnings:

• Disconnect the battery before working on electrical systems.
• Allow the engine to cool before performing maintenance to prevent burns.