how to fix P0301 misfire code in my Volvo XC90 Second Generation (2015-2024)?

Solution

1. Preparation

• Gather tools and parts.
• Disconnect the negative battery terminal to prevent electrical shock.
• Allow engine to cool to avoid burns.

2. Replace Spark Plug

• Tools Required: Spark plug socket, ratchet, torque wrench.
• Remove the ignition coil by unscrewing any retaining bolts and unplugging the electrical connector.
• Use the spark plug socket to remove the old spark plug.
• Inspect the spark plug gap; adjust if necessary, or install a new spark plug.
• Torque the new spark plug to the manufacturer's specifications (typically around 13-16 lb-ft).
• Reinstall the ignition coil and reconnect the electrical connector.

3. Test or Replace Ignition Coil

• If swapping the ignition coil with another cylinder, check for misfire code change.
• If the coil is faulty, replace it with a new one.
• Ensure the new ignition coil is properly seated and connected.

4. Inspect Fuel Injector

• Remove the fuel injector from cylinder 1 (refer to vehicle service manual for specific removal procedures).
• Use a multimeter to test the injector resistance; replace if out of specification.
• Clean the injector with an appropriate cleaner if it appears clogged.
• Reinstall the injector and ensure proper connection.

5. Address Compression Issues

• If compression is low, consider a more detailed inspection of engine components, such as valve seals or piston rings.
• If necessary, consult a professional for internal engine repairs.