how to fix P0301 misfire code in my Toyota Camry XV40 (2007-2011)

Solution

1. Preparation

• Gather necessary tools and parts.
• Ensure the vehicle is parked on a flat surface and the engine is cool.
• Disconnect the negative battery terminal to prevent electrical shorts.

2. Inspect and Replace Spark Plug

• Tools Required: Socket set, torque wrench, spark plug socket.
• Remove the ignition coil from cylinder 1:
  1. Unscrew the bolts securing the ignition coil and carefully lift it out.
  2. Disconnect the electrical connector from the ignition coil.
• Remove the spark plug using a spark plug socket.
• Inspect the spark plug for fouling or wear. Replace if necessary:
  1. Gap the new spark plug according to manufacturer specifications (typically 0.043 inches for the Camry).
  2. Install the new spark plug and torque to 13 lb-ft (17.6 Nm).
• Reinstall the ignition coil and reconnect the electrical connector.

3. Check and Replace Ignition Coil

• Tools Required: Socket set, torque wrench.
• If the spark plug is in good condition, test the ignition coil:
  1. Use a multimeter to check resistance according to specifications (usually 0.5-0.6 ohms for primary resistance).
  2. If out of specification, replace the ignition coil with a new unit.
• Reinstall the ignition coil and ensure secure connection.

4. Inspect Fuel Injector

• Tools Required: Fuel injector cleaning kit or replacement injectors.
• Check the fuel injector for cylinder 1:
  1. Remove the fuel rail if necessary to access the injector.
  2. Perform a resistance test or listen for clicking sounds while the engine is running.
• Replace the injector if faulty, ensuring proper sealing and connection.

5. Perform Compression Test

• Tools Required: Compression tester.
• Conduct a compression test on cylinder 1:
  1. Remove the spark plug for cylinder 1.
  2. Insert the compression tester and crank the engine.
  3. Record and compare compression reading to manufacturer specifications (typically 180-200 psi).
• If compression is low, further investigation into valve seating or piston ring condition may be necessary.