why is my Honda Accord 8th Generation (2008-2012) engine misfiring when accelerating

Learn how to diagnose and fix engine misfires during acceleration in Honda Accord 2008-2012. Step-by-step guide with diagnostic procedures and repair instructions.

Solution

1. Preparation

• Gather necessary tools and parts.
• Disconnect the battery to ensure safety while working on the ignition system.

2. Inspect and Replace Spark Plugs

• Sub-steps:
  • Remove the ignition coil covers.
  • Carefully extract the spark plugs using a spark plug socket.
  • Inspect the spark plugs for wear, carbon deposits, or damage.
  • Replace spark plugs with OEM or equivalent parts, ensuring proper gap settings (typically 0.044 inches).
  • Reinstall the ignition coils and covers.

3. Test and Replace Ignition Coils (if necessary)

• Sub-steps:
  • Remove the ignition coils from the spark plugs.
  • Test each coil with a multimeter to check for proper resistance (typically 0.4-2.0 ohms).
  • Replace any faulty ignition coils with new ones, ensuring the correct part number matches your vehicle's specifications.

4. Fuel Injector Inspection and Cleaning

• Sub-steps:
  • Connect a fuel pressure gauge to the fuel rail to check for proper fuel pressure (should be within manufacturer's specifications, around 40-50 psi).
  • If pressure is low, inspect the fuel pump and filter for clogs.
  • Consider using a fuel injector cleaner or ultrasonic cleaning service if injectors are clogged.

5. Air Intake System Inspection

• Sub-steps:
  • Visually inspect the air intake hoses for cracks or looseness.
  • Ensure that the air filter is clean and replace it if dirty.
  • Check the Mass Air Flow (MAF) sensor for dirt and clean it with MAF sensor cleaner.

6. Compression Test (if misfire persists)

• Sub-steps:
  • Remove spark plugs and install a compression gauge in each cylinder.
  • Crank the engine and record the compression readings.
  • If readings are low, further engine diagnostics may be necessary to check for valve issues or head gasket failure.

Tools Required:

• OBD-II scanner
• Spark plug socket
• Multimeter
• Fuel pressure gauge
• Torque wrench
• Basic hand tools (sockets, wrenches)

Parts Required:

• Spark plugs
• Ignition coils (if needed)
• Fuel filter (if needed)
• Air filter

Estimated Repair Time: 2-4 hours

Safety Warnings:

• Disconnect battery before working on electrical systems.
• Allow engine to cool before starting work.