my Toyota Highlander has a check engine light with code P0302, what does it mean?

Solution

1. Preparation

• Gather tools and parts required for the repair.
• Disconnect the battery to ensure safety while working on electrical components.
• Allow the engine to cool before proceeding with repairs.

2. Inspect and Replace Spark Plug

• Tools Required: Socket set, torque wrench, spark plug socket.
• Remove the engine cover if necessary.
• Use the spark plug socket to remove the spark plug from cylinder 2.
  • Sub-step: Inspect the spark plug for wear, carbon buildup, or damage.
  • Sub-step: If worn or damaged, replace with a new spark plug of the correct specification (refer to owner’s manual for gap settings).
• Reinstall the spark plug, tightening to the manufacturer’s torque specification.

3. Inspect and Replace Ignition Coil

• Tools Required: Socket set, torque wrench.
• Remove the ignition coil from cylinder 2 by unscrewing the bolts securing it.
  • Sub-step: Inspect the ignition coil for cracks or electrical issues.
  • Sub-step: If faulty, replace with a new ignition coil specific to the Toyota Highlander.
• Reinstall the ignition coil and secure it with the bolts, tightening to the manufacturer’s specification.

4. Test Fuel Injector

• Tools Required: Fuel injector tester (or multimeter).
• Disconnect the fuel injector connector for cylinder 2.
• Use the fuel injector tester to check the injector's operation.
  • Sub-step: If the injector is not functioning correctly, replace it with a new one.
• Reconnect the injector connector after testing.

5. Compression Test

• Tools Required: Compression tester.
• Remove the spark plug and ignition coil from cylinder 2.
• Insert the compression tester into the spark plug hole and crank the engine to take a reading.
  • Sub-step: Compare the reading with manufacturer specifications. If the compression is low, further diagnostics may be needed to check for internal engine issues.