how to diagnose P0302 code in Toyota Highlander XU70 (2020-Present)

Solution

1. Preparation

• Gather tools and parts required for the repair.
• Disconnect the negative battery terminal to ensure safety.
• Allow the engine to cool before starting work.

2. Inspect and Replace Ignition Coil

• Sub-steps:
  1. Remove the engine cover if applicable.
  2. Disconnect the electrical connector from the ignition coil for cylinder 2.
  3. Remove the ignition coil using a socket set (typically 10mm bolts).
  4. Inspect the coil for cracks or signs of arcing.
  5. If defective, replace the ignition coil with a new one.
  6. Reinstall the ignition coil and reconnect the electrical connector.

3. Inspect and Replace Spark Plug

• Sub-steps:
  1. Remove the ignition coil from cylinder 2 as described in the previous step.
  2. Use a spark plug socket to remove the spark plug from cylinder 2.
  3. Inspect the spark plug for wear, deposits, or damage.
  4. Replace with a new spark plug if necessary, ensuring it is gapped according to manufacturer specifications.
  5. Reinstall the spark plug and the ignition coil.

4. Inspect and Clean Fuel Injector

• Sub-steps:
  1. Locate and disconnect the fuel injector connector for cylinder 2.
  2. Remove the fuel injector from the fuel rail (check for any retaining clips).
  3. Inspect the injector for clogs or damage.
  4. Clean the injector using an appropriate cleaning solution or replace with a new injector if heavily clogged.
  5. Reinstall the injector and reconnect the electrical connector.

5. Conduct Compression Test (if necessary)

• Sub-steps:
  1. Remove the spark plug from cylinder 2.
  2. Insert a compression gauge into the spark plug hole.
  3. Crank the engine to obtain a compression reading.
  4. Compare the reading to manufacturer specifications. If low, further investigation into engine internals may be required.

Tools Required:

• OBD-II scanner
• Socket set (including spark plug socket)
• Torque wrench
• Compression gauge
• Fuel injector cleaning kit (if cleaning is necessary)

Parts Required:

• Ignition coil for cylinder 2
• Spark plug for cylinder 2
• Fuel injector for cylinder 2 (if replacement is necessary)

Estimated Repair Time: 2-4 hours

Safety Warnings:

• Disconnect the battery before working on electrical systems.
• Allow the engine to cool before opening any engine components.