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

Solution

1. Preparation

• Gather all necessary tools and parts.
• Ensure the engine is cool before beginning work.
• Disconnect the negative battery terminal to avoid electrical shock.

2. Inspect and Replace Spark Plug

1. Remove the engine cover (if applicable).
2. Remove the ignition coil by unscrewing the retaining bolt and disconnecting the electrical connector.
3. Carefully unscrew the spark plug using a spark plug socket and ratchet.
4. Inspect the spark plug for wear, fouling, or damage. Replace if necessary.
5. Install a new spark plug, ensuring it is gapped correctly (0.043 inches for most 2.4L engines).
6. Reattach the ignition coil and bolt it back in place.

3. Check and Replace Ignition Coil (if necessary)

1. If the spark plug inspection indicates the coil is faulty, remove it by unscrewing the retaining bolt and disconnecting the connector.
2. Install a new ignition coil, ensuring it is seated properly.
3. Reconnect the electrical connector and secure it with the retaining bolt.

4. Inspect Fuel Injector

1. Remove the fuel rail if needed for access, making sure to relieve fuel pressure beforehand.
2. Inspect the fuel injector in cylinder 1 for clogs or damage.
3. Clean the injector using a fuel injector cleaner or replace it if necessary.
4. Reassemble the fuel rail and ensure all connections are secure.

5. Test Compression (if necessary)

1. If misfire persists, perform a compression test on cylinder 1.
2. If compression is low, further investigation into valves or piston rings may be needed.