my Honda Accord has a check engine light and runs rough, what should I do

Solution

1. Preparation

• Gather all necessary tools and parts.
• Disconnect the battery to ensure safety while working on electrical components.
• Allow the engine to cool if it has been running.

2. Address Ignition System

• Inspect Spark Plugs:

  • Remove spark plug wires using a spark plug socket.
  • Inspect spark plugs for fouling or excessive wear.
  • Replace spark plugs if necessary with OEM specifications (e.g., NGK or Denso).

• Test Ignition Coils:

  • Remove ignition coil(s) connected to the affected cylinder(s).
  • Using a multimeter, check resistance according to manufacturer specifications.
  • Replace any faulty ignition coils.

3. Check Fuel System

• Fuel Pressure Test:
  • Connect the fuel pressure gauge to the fuel rail.
  • Turn the ignition to the "on" position (without starting the engine) and check pressure.
  • Compare the reading with manufacturer specifications; replace the fuel pump if pressure is low.

4. Inspect Air Intake and Vacuum System

• Air Intake Inspection:

  • Remove the air intake duct and inspect the air filter; replace if dirty.
  • Check for any air leaks in the intake manifold.

• Vacuum Line Inspection:

  • Visually inspect all vacuum hoses for cracks or disconnections.
  • Replace any damaged hoses.

5. Reassemble and Connect Battery

• Reinstall all components in reverse order of removal.
• Reconnect the negative terminal of the battery.