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

Solution

1. Preparation

• Gather tools and parts: OBD-II scanner, socket set, torque wrench, compression tester, multimeter, spark plug socket, and replacement parts as necessary.
• Disconnect the negative battery terminal to prevent electrical shorts.

2. Inspect and Replace Spark Plug

• Remove the ignition coil cover (if applicable) using a socket set.
• Use a spark plug socket to remove the spark plug from cylinder 1.
• Inspect the spark plug for wear, carbon buildup, or damage. Replace if necessary.
• Install a new spark plug, ensuring it is gapped correctly (usually around 0.044 inches).
• Torque the spark plug to manufacturer specifications (typically around 13-15 lb-ft).

3. Check and Replace Ignition Coil

• Remove the ignition coil from cylinder 1 by unscrewing it and disconnecting the electrical connector.
• Test the ignition coil using a multimeter to check for proper resistance (consult service manual for specific values).
• If the ignition coil is faulty, install a new one by reversing the removal steps and ensuring tight connections.

4. Inspect and Replace Fuel Injector

• Disconnect the fuel injector connector for cylinder 1.
• Check injector operation using a noid light; if it does not light up, the injector is likely faulty.
• Remove the fuel rail to access the injector, following the service manual for specific disassembly procedures.
• Replace the faulty fuel injector with a new one, applying a small amount of engine oil to the O-ring to ensure a proper seal.
• Reassemble the fuel rail and reconnect all connectors.

5. Verify Compression

• If misfire persists, perform a compression test on cylinder 1.
• If the compression is below specifications (usually around 180 psi), further investigation into valve or piston issues may be necessary.