how to fix P0300 code in Toyota RAV4 Fourth Generation (2013-2018)

Solution

1. Preparation

• Gather tools and materials: OBD-II scanner, multimeter, spark plug socket, torque wrench, fuel pressure gauge, and basic hand tools.
• Disconnect the battery to ensure safety while working on electrical components.

2. Inspect and Replace Spark Plugs

• Remove the ignition coils using a socket wrench.
• Take out the spark plugs with a spark plug socket.
  • Tools Required: Spark plug socket, extension bar
• Inspect the spark plugs for wear (e.g., carbon buildup, electrode wear).
• Replace spark plugs if necessary, ensuring that the gap is set to the manufacturer's specifications.
  • Torque: Tighten spark plugs to 13 lb-ft (18 Nm).

3. Check and Replace Ignition Coils

• Visually inspect the ignition coils for cracks or carbon tracking.
• Test the resistance of each coil using a multimeter.
  • Specification: Primary resistance should be around 0.4 to 2.0 ohms, and secondary resistance should be around 6,000 to 15,000 ohms.
• Replace any faulty ignition coils with new units, ensuring they are correctly seated.

4. Fuel System Inspection

• Connect a fuel pressure gauge to the fuel rail and turn the ignition to the "on" position (do not start the engine).
• Verify that fuel pressure is within the manufacturer's specifications (usually around 50-60 psi for RAV4).
• If pressure is low, inspect the fuel pump, filter, and injectors for issues.
• Replace any faulty components as necessary.

5. Compression Test

• Remove the spark plugs to facilitate the compression test.
• Insert the compression gauge into each cylinder and crank the engine.
• Record the compression readings for each cylinder.
  • Specification: Compression should be around 170-220 psi.
• If any cylinder has significantly lower compression, further investigation (such as checking for leaks) may be required.