how to diagnose P0301 misfire code on Toyota Camry Eighth Generation (2018-present)

Solution

1. Preparation

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

2. Inspect and Replace Spark Plug

• Remove the ignition coil from cylinder 1 by unscrewing the retaining bolt and disconnecting the electrical connector.
• Remove the spark plug using a spark plug socket and ratchet. Inspect it for wear or damage.
• If the spark plug is worn, replace it with an OEM equivalent. Ensure it is gapped correctly as per the manufacturer's specifications.
• Reinstall the spark plug and secure the ignition coil back in place.

3. Check and Replace Ignition Coil (if needed)

• If the ignition coil shows signs of damage (e.g., cracks or corrosion), replace it with a new coil.
• Ensure proper seating and connection of the ignition coil to the spark plug and the electrical connector.

4. Inspect Fuel Injector

• Disconnect the fuel injector connector for cylinder 1.
• Using a multimeter, check the resistance of the injector to ensure it meets specifications (typically between 12-16 ohms).
• If the injector is faulty, replace it with a new one, ensuring proper installation and connection.

5. Perform Compression Test

• Remove spark plugs from all cylinders for a more accurate test.
• Insert a compression gauge into cylinder 1 and crank the engine to record the pressure.
• Compare the reading to the manufacturer's specifications. If the reading is low, further investigation into internal engine components may be needed.