how to diagnose a P0301 code on my Toyota Camry XV70 (2018-2024)

Solution

1. Preparation

• Gather all necessary tools and parts.
• Park the vehicle on a flat surface and engage the parking brake.
• Disconnect the negative battery terminal to ensure safety during repairs.

2. Inspect and Replace Spark Plug

• Remove the ignition coil from cylinder 1:
  • Remove the bolts securing the coil and detach the electrical connector.
• Remove the spark plug using a spark plug socket:
  • Check the spark plug for wear or damage, and replace if necessary with OEM specifications (typically, NGK or Denso for Toyota).
• Install the new spark plug:
  • Torque to the manufacturer’s specification (usually around 13-16 lb-ft).

3. Check and Replace Ignition Coil

• If the spark plug is in good condition, inspect the ignition coil:
  • Use a multimeter to check the primary and secondary resistance of the coil.
• Replace the ignition coil if it fails the test:
  • Reinstall the new coil and reconnect the electrical connector.

4. Inspect and Replace Fuel Injector

• If the ignition components are functioning correctly, inspect the fuel injector:
  • Remove the fuel rail cover and disconnect the fuel line.
  • Remove the injector from the rail and check for clogs.
• Replace with a new fuel injector if necessary:
  • Ensure proper seating and reattach all connections.

5. Perform Compression Test

• If misfire persists, perform a compression test:
  • Remove the spark plug and install the compression tester.
  • Crank the engine and record the compression reading.
• If compression is low, further investigation into the piston rings or valves may be required.