what does it mean if my Volkswagen Golf MK7.5 (2020-Present) shows a P0303 code

Solution

1. Preparation

• Gather all necessary tools and parts.
• Disconnect the negative battery terminal to prevent electrical shorts.
• Allow engine components to cool before starting work.

2. Inspect and Replace Ignition Components

• Tools Required: Socket set, torque wrench, spark plug socket
• Remove the ignition coil from cylinder 3:
  1. Unscrew the bolts securing the ignition coil.
  2. Disconnect the electrical connector.
  3. Pull the ignition coil straight out.
• Check the spark plug:
  1. Remove the spark plug using a spark plug socket.
  2. Inspect for signs of wear or damage (e.g., burning, deposits).
  3. Replace the spark plug if necessary with the manufacturer-recommended type (typically around 0.028 inches gap).

3. Check and Clean Fuel Injector

• Tools Required: Fuel injector cleaner, safety goggles
• Remove the fuel injector for cylinder 3:
  1. Depressurize the fuel system.
  2. Disconnect the fuel line and electrical connector.
  3. Remove the retaining clips and pull out the injector.
• Clean the injector using a fuel injector cleaning kit or replace it if clogged or faulty.

4. Conduct Compression Test (if necessary)

• Tools Required: Compression tester
• Insert the compression tester into the spark plug hole of cylinder 3:
  1. Crank the engine for a few seconds.
  2. Record the compression reading.
• Compare the reading with manufacturer specifications (typically between 130-200 psi). If the compression is low, further internal engine diagnosis may be required.

5. Reassemble and Test

• Reinstall all components in reverse order of removal.
• Reconnect the negative battery terminal.
• Start the engine and monitor for any misfire codes.