how to fix P0300 code in Toyota Corolla E170 (2013-2019)

Solution

1. Preparation

• Gather necessary tools and parts.
• Disconnect the negative battery terminal to ensure safety.
• Allow the engine to cool before beginning any work.

2. Inspect and Replace Spark Plugs

• Remove the ignition coils using a socket wrench.
• Take out the spark plugs using a spark plug socket.
• Inspect the spark plugs for wear. Replace if worn or fouled.
• Install new spark plugs, tightening to manufacturer specifications (typically around 13-15 lb-ft).

3. Inspect and Replace Ignition Coils

• If spark plugs are fine, check ignition coils for proper function.
• Disconnect the electrical connector and unbolt the ignition coil.
• Replace any faulty ignition coils with new ones.
• Reconnect the electrical connectors.

4. Check Fuel System

• Use a fuel pressure gauge to measure fuel pressure at the rail.
• If pressure is low, inspect the fuel filter and fuel pump.
• Replace the fuel filter if clogged and consider replacing the fuel pump if it fails to provide adequate pressure.

5. Inspect Air Intake and Vacuum System

• Check the air intake for any obstructions or leaks.
• Inspect all vacuum lines for cracks or disconnections; repair or replace as necessary.

6. Clear Codes and Test Drive

• Reconnect the battery terminal.
• Use the OBD-II scanner to clear the P0300 code.
• Start the engine and take the vehicle for a test drive to ensure the issue is resolved.