how to address a P0301 misfire code on my Toyota Corolla E170 (2013-2019)?

Solution

1. Preparation

• Gather all necessary tools and parts.
• Disconnect the negative battery terminal to prevent any electrical shorts during repairs.
• Allow the engine to cool if it has been running.

2. Replace Spark Plug

• Remove the ignition coil from cylinder 1.
  • Tools Required: Ratchet and socket set.
• Unscrew and remove the spark plug using a spark plug socket.
• Inspect the spark plug; if worn or damaged, replace it with a new one.
  • Torque Specification: 13 lb-ft for spark plug installation.
• Reinstall the ignition coil onto the new spark plug.

3. Inspect and/or Replace Ignition Coil

• If the ignition coil is suspected to be faulty, disconnect the electrical connector and remove the coil.
• Test the coil's primary and secondary resistance using a multimeter.
• If out of specification, replace the ignition coil with a new one.
  • Tools Required: Ratchet and socket set.

4. Inspect Fuel Injector

• Locate the fuel injector for cylinder 1 and disconnect the electrical connector.
• Remove the fuel rail, if necessary, to access the injector.
• Clean the injector using a specialized fuel injector cleaner or replace it if clogged or malfunctioning.
• Reinstall the fuel rail and reconnect the injector.

5. Compression Test

• Remove the spark plug from cylinder 1 to access the combustion chamber.
• Insert a compression gauge into the spark plug hole and crank the engine to measure compression.
• If the compression is low, assess for potential internal engine problems (valve issues, head gasket failure).