how to fix P0301 code on my Volkswagen Golf Eighth Generation (2020-present)

Solution

1. Preparation

• Gather tools and parts: OBD-II scanner, socket set, torque wrench, compression tester, fuel injector cleaner, and replacement parts (if needed).
• Disconnect the negative battery terminal to ensure safety.

2. Inspect Spark Plugs

• Remove the engine cover (if applicable) using a socket set.
• Disconnect the ignition coil connector for cylinder 1.
• Remove the ignition coil and spark plug from cylinder 1 using the appropriate socket.
• Inspect the spark plug for wear; replace if necessary (gapping should be according to manufacturer specifications).
• Reinstall the spark plug and ignition coil, ensuring they are torqued to the specified values.

3. Check Ignition Coil

• Swap the ignition coil from cylinder 1 with one from another cylinder (e.g., cylinder 2).
• Clear the code using the OBD-II scanner and start the engine.
• Monitor if the misfire code shifts to the other cylinder. If it does, replace the ignition coil.

4. Compression Test

• With the spark plug removed, use a compression tester to check cylinder 1's compression.
• If the compression is below the manufacturer's specifications, further inspection of the piston rings, valves, or head gasket is needed.

5. Inspect Fuel Injector

• Remove the fuel rail to access the fuel injector for cylinder 1.
• Inspect the injector for clogs or leaks. Clean with a fuel injector cleaner if necessary.
• Test the injector's resistance with a multimeter; replace if out of specifications.

6. Check for Vacuum Leaks

• Visually inspect vacuum hoses and the intake manifold for cracks or disconnections.
• Use a smoke machine to detect leaks if necessary.