how to diagnose a misfire in my Toyota RAV4 Fifth Generation (2019-present)

Solution

1. Preparation

• Gather necessary tools and parts for the repair.
• Ensure the vehicle is on a flat surface and the engine is cool.
• Disconnect the negative battery terminal to prevent electrical shorts.

2. Replace Spark Plugs

1. Remove the engine cover (if applicable) using a socket and ratchet.
2. Disconnect the ignition coil connectors.
3. Unbolt the ignition coils using a socket and ratchet and remove them carefully from the spark plug wells.
4. Use a spark plug socket to remove the old spark plugs.
5. Inspect the new spark plugs for proper gap (typically 0.044 inches for RAV4) and install them, tightening to 13 lb-ft (17 Nm).
6. Reinstall the ignition coils, reattach the connectors, and secure the engine cover.

3. Test and Replace Ignition Coils (if necessary)

1. If misfire codes indicate a specific cylinder, replace the corresponding ignition coil.
2. Remove the coil as described in the previous step.
3. Install the new ignition coil and secure it with bolts.
4. Reconnect the ignition coil connector.

4. Fuel System Inspection

1. Connect a fuel pressure gauge to the fuel rail service port.
2. Turn the ignition to the "ON" position (not starting the engine) to check the fuel pressure.
3. Refer to specifications (typically around 50-60 psi for RAV4) and replace the fuel pump or filter if pressure is low.

5. Final Assembly

• Reconnect the negative battery terminal.
• Start the engine to ensure it runs smoothly and without misfire.