how to diagnose a P0302 code on my Toyota Highlander Third Generation (2014-2019)?

Solution

1. Preparation

• Gather tools and parts required for the repair.
• Ensure the engine is cool and disconnect the negative battery cable to prevent any electrical shorts.

2. Replace Spark Plug (if found faulty)

• Remove the engine cover (if applicable) using a socket set.
• Disconnect the ignition coil connector and remove the ignition coil from cylinder 2.
• Use a spark plug socket to remove the spark plug; inspect and replace with a new one if needed. Torque the new spark plug to the manufacturer's specification (typically 13-15 lb-ft).
• Reinstall the ignition coil and reconnect the connector.

3. Replace Ignition Coil (if found faulty)

• After removing the ignition coil from cylinder 2, compare it to a new coil.
• If faulty, install the new ignition coil, ensuring it is seated correctly.
• Reconnect the ignition coil connector and ensure it clicks into place.

4. Clean or Replace Fuel Injector (if found faulty)

• Remove the fuel injector from cylinder 2 by disconnecting the electrical connector and the fuel line (use caution as fuel may spill).
• Inspect the injector for clogs; clean or replace as necessary.
• Reinstall the fuel injector, ensuring it is seated properly, and reconnect any hoses or electrical connectors.

5. Perform Compression Test (if mechanical issues are suspected)

• Remove the spark plug from cylinder 2 and insert the compression gauge.
• Crank the engine and record the compression reading; compare it to specifications (typically around 180 psi).
• If low, further investigation may be needed for valve or piston issues.