how to fix P0303 code in Toyota RAV4 Fifth Generation (2019-present)

Solution

1. Preparation

• Gather necessary tools and parts.
• Park the vehicle on a flat surface and engage the parking brake.
• Disconnect the negative battery terminal to avoid electrical shorts.

2. Replace Spark Plug

• Tools Required: Socket set, torque wrench, spark plug socket.
• Remove the engine cover if present.
• Locate the spark plug for cylinder 3 (refer to the owner's manual for cylinder numbering).
• Use the spark plug socket to unscrew and remove the old spark plug.
• Inspect the old spark plug for signs of fouling or wear.
• Install the new spark plug and torque it to the manufacturer’s specifications (typically around 13-20 lb-ft).

3. Test and Replace Ignition Coil

• Tools Required: Socket set.
• Remove the ignition coil from cylinder 3 by unbolting it and disconnecting the electrical connector.
• Test the ignition coil using a multimeter to check for proper resistance (refer to service manual specifications).
• If faulty, replace with a new ignition coil.
• Reinstall the ignition coil, ensuring it is seated properly and reconnected.

4. Inspect and Clean Fuel Injector

• Tools Required: Fuel injector cleaning kit or replacement injector.
• Disconnect the fuel line and electrical connector from the cylinder 3 fuel injector.
• Remove the injector from the rail.
• If cleaning, use a fuel injector cleaning kit to flush the injector; if replacing, install a new injector.
• Reconnect the fuel line and electrical connector securely.

5. Conduct Compression Test

• Tools Required: Compression tester.
• Remove the spark plug from cylinder 3.
• Insert the compression tester into the spark plug hole and crank the engine.
• Note the pressure reading; it should be within the manufacturer’s specified range (typically 150-200 psi).
• If compression is low, further investigation into engine internals may be required.