how to resolve P0301 misfire code on my Toyota Corolla E170 (2013-2019)

Solution

1. Preparation

• Gather necessary tools and parts.
• Disconnect the negative battery terminal to prevent electrical shorts.
• Allow the engine to cool down completely before beginning work.

2. Inspect and Replace Spark Plug

• Tools Required: Socket set, torque wrench, spark plug socket.
• Remove the ignition coil cover if applicable.
• Disconnect the ignition coil connector and remove the ignition coil.
• Unscrew and remove the spark plug from cylinder 1.
• Inspect the spark plug for fouling or wear. Replace it if necessary.
• Install a new spark plug, torquing it to manufacturer's specifications (typically around 13 lb-ft).

3. Inspect and Replace Ignition Coil

• If the spark plug is in good condition, inspect the ignition coil for cracks or damage.
• Tools Required: Socket set.
• Remove the ignition coil from cylinder 1.
• Replace the ignition coil with a new one and reconnect the ignition coil connector.

4. Check and Clean Fuel Injector

• Remove the fuel injector for cylinder 1.
• Tools Required: Fuel injector puller (if necessary).
• Inspect the injector for clogs or damage. Clean or replace the injector as needed.
• Reinstall the fuel injector and ensure proper connections.

5. Compression Test

• Insert a compression gauge into the spark plug hole of cylinder 1.
• Crank the engine and record the compression reading.
• If the compression is below manufacturer specifications, further investigation into internal engine issues may be necessary.

6. Reassemble and Reconnect

• Reinstall any components removed for access, including the ignition coil cover.
• Reconnect the negative battery terminal.