how to fix engine misfire P0303 code Volkswagen Passat B8 (2015-2022)

Learn how to diagnose and fix P0303 cylinder 3 misfire in Volkswagen Passat B8 (2015-2022). Step-by-step guide with diagnostic procedures and repair instructions.

Solution

1. Preparation

• Gather all necessary tools and parts.
• Disconnect the negative battery terminal to ensure safety while working on the electrical components.

2. Replace Spark Plug

• Remove the ignition coil from cylinder 3:
  • Unscrew the bolts holding the ignition coil using a socket set.
  • Gently pull the ignition coil out of the spark plug socket.
• Remove the spark plug:
  • Use a spark plug socket to unscrew and remove the old spark plug.
• Install a new spark plug:
  • Apply anti-seize lubricant to the threads of the new spark plug.
  • Torque to manufacturer specifications (typically around 20 Nm / 15 lb-ft).

3. Replace Ignition Coil (if necessary)

• If the ignition coil appears defective, replace it:
  • Install the new ignition coil onto the spark plug.
  • Secure it with bolts and reconnect the electrical connector.

4. Check Fuel Injector

• If the injector is faulty:
  • Disconnect the fuel line and electrical connector from the injector.
  • Remove the old fuel injector using appropriate tools.
  • Install the new fuel injector and reconnect the fuel line and electrical connection.

5. Reassemble and Test

• Reconnect the negative battery terminal.
• Start the engine and check for any error codes.
• Test drive the vehicle to confirm the misfire has been resolved.