how to fix P0301 misfire code on my Volkswagen Golf MK7.5 (2020-Present)

Solution

1. Preparation

• Gather tools and parts, ensuring the area is clean and organized.
• Disconnect the battery to prevent electrical shorts.
• Gather necessary tools: OBD-II scanner, socket set, torque wrench, compression tester, multimeter, and vacuum gauge.

2. Replace Spark Plug

• Sub-steps:
  1. Remove the ignition coil from cylinder 1 using a socket wrench.
  2. Remove the spark plug using a spark plug socket and ratchet.
  3. Inspect the old spark plug for signs of wear; replace if damaged.
  4. Install the new spark plug, ensuring the correct gap (usually 0.028-0.031 inches for this engine).
  5. Torque the spark plug to the manufacturer's specification (usually around 22 lb-ft).

3. Inspect and Replace Ignition Coil

• Sub-steps:
  1. If the spark plug was okay, test the ignition coil by swapping it with another cylinder.
  2. If the misfire moves to the new cylinder, replace the ignition coil.
  3. Install the new ignition coil by pushing it down into the spark plug well until it clicks into place.
  4. Reconnect the ignition coil connector.

4. Check and Replace Fuel Injector

• Sub-steps:
  1. Disconnect the fuel injector connector on cylinder 1.
  2. Use a multimeter to check the injector's resistance; it should match specifications (typically around 12-16 ohms).
  3. If out of spec, replace the fuel injector.
  4. Install the new injector and reconnect the fuel line and connector.

5. Verify Compression

• Sub-steps:
  1. Remove the spark plug from cylinder 1 again.
  2. Insert the compression tester into the spark plug hole.
  3. Crank the engine for a few seconds and record the compression reading.
  4. Compare the reading with the manufacturer's specifications (typically around 180-200 psi). If low, further investigation into engine internals is required.