how to fix P0303 misfire code on Volkswagen Golf MK7 (2015-2019)

Solution

1. Preparation

• Gather necessary tools and parts.
• Park the vehicle on a flat surface and set the parking brake.
• Disconnect the negative battery terminal to prevent electrical shocks.

2. Inspect and Replace Spark Plug

• Tools Required: Socket set, torque wrench
• Remove the ignition coil from cylinder 3:
  1. Disconnect the electrical connector from the ignition coil.
  2. Unscrew the bolts holding the ignition coil.
  3. Remove the ignition coil.
• Remove the spark plug:
  1. Use a spark plug socket to unscrew and remove the spark plug from cylinder 3.
  2. Inspect the spark plug for wear or fouling; replace it if necessary.
• Install the new spark plug:
  1. Apply a small amount of anti-seize compound to the threads (optional).
  2. Hand-tighten the spark plug, then use the torque wrench to tighten it to the manufacturer's specified torque (typically around 22 lb-ft).

3. Inspect and Replace Ignition Coil

• If the ignition coil shows signs of damage or wear:
  1. Install the new ignition coil onto the spark plug and secure it with bolts.
  2. Reconnect the electrical connector to the ignition coil.

4. Inspect Fuel Injector

• If the injector is found to be faulty:
  1. Disconnect the fuel line (ensure the system is depressurized).
  2. Remove the fuel injector from the rail.
  3. Install the new fuel injector and reconnect the fuel line.

5. Clear Codes and Test Drive

• Reconnect the negative battery terminal.
• Use the OBD-II scanner to clear the P0303 code.
• Test drive the vehicle to ensure the issue is resolved.