how to fix a misfire in my Toyota Highlander Fourth Generation (2020-present) with code P0302

Solution

1. Preparation

• Gather all necessary tools and parts.
• Disconnect the negative terminal of the battery to ensure safety.

2. Inspect and Replace Spark Plug

• Remove the ignition coil cover if applicable.
• Disconnect the electrical connector from the ignition coil for cylinder 2.
• Remove the ignition coil using a socket set.
• Inspect the spark plug; if it appears worn or damaged, replace it.
  • Torque the new spark plug to 13 lb-ft (17.6 Nm).
• Reinstall the ignition coil and reconnect the electrical connector.

3. Inspect and Replace Fuel Injector

• Remove any components obstructing access to the fuel injector for cylinder 2 (e.g., intake manifold).
• Disconnect the fuel injector connector and fuel line (ensure to relieve fuel pressure first).
• Remove the retaining clip and extract the fuel injector.
• Inspect the old injector for clogs; replace if necessary with a new one.
• Reinstall the fuel injector and reconnect the fuel line and electrical connector securely.

4. Check and Replace Ignition Coil

• If the ignition coil for cylinder 2 appears damaged during inspection, replace it.
• Simply remove the faulty ignition coil and install the new one, ensuring it is seated properly.
• Reconnect the electrical connector.

5. Final Assembly and Connection

• Reassemble any components that were removed, ensuring all bolts are torqued to manufacturer specifications.
• Reconnect the negative terminal of the battery.