how to diagnose the engine misfire code P0302 on my Toyota RAV4

Solution

1. Preparation

• Gather all necessary tools and parts.
• Ensure the vehicle is parked on a level surface, and the engine is cool.
• Disconnect the negative battery terminal to prevent electrical shock.

2. Inspect and Replace Spark Plug

• Remove the spark plug wire or ignition coil from cylinder 2.
• Use a spark plug socket and ratchet to remove the spark plug.
• Inspect the spark plug for fouling, wear, or damage. If necessary, replace it with a new spark plug to the manufacturer’s specifications (typically torque to 13 lb-ft).
• Reinstall the ignition component.

3. Inspect and Replace Ignition Coil

• Remove the ignition coil from cylinder 2 by unscrewing the bolts holding it in place.
• Inspect the coil for cracks or damage. If faulty, replace with a new ignition coil.
• Reinstall the ignition coil and ensure it is properly seated.

4. Inspect Fuel Injector

• Disconnect the fuel injector connector for cylinder 2.
• Remove the fuel injector using an injector puller or a suitable tool.
• Inspect the O-rings for wear and replace if necessary. Clean the injector or replace it if it is clogged or malfunctioning.
• Reinstall the fuel injector and reconnect the electrical connector.

5. Perform Compression Test

• Remove the spark plug from cylinder 2.
• Use a compression gauge to measure the compression in cylinder 2.
• Compare the reading to the manufacturer’s specifications. If low, further diagnostics may be required.

6. Test Fuel Pressure

• Connect a fuel pressure gauge to the fuel rail.
• Turn the ignition on without starting the engine and check the fuel pressure reading. It should match the manufacturer’s specification.
• If pressure is low, inspect the fuel pump and fuel filter for issues.