how to fix the 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 electrical shock.

2. Replace Spark Plug

1. Remove the engine cover if applicable.
2. Using a spark plug socket, remove the spark plug from cylinder 1.
3. Inspect the old spark plug for wear; replace it with a new spark plug if necessary.
   • Torque the new spark plug to manufacturer specifications (typically around 13-15 lb-ft).
4. Reinstall the engine cover.

3. Inspect and Replace Ignition Coil

1. Disconnect the electrical connector from the ignition coil for cylinder 1.
2. Remove the mounting bolts for the ignition coil using a socket wrench.
3. Pull the ignition coil out gently; inspect for cracks or damage.
4. Install a new ignition coil by reversing the removal process.
   • Ensure it is seated properly and torque the bolts to manufacturer specifications.

4. Test Fuel Injector

1. Disconnect the fuel injector connector for cylinder 1.
2. Use a noid light to check for signal at the connector; replace the injector if no signal is present.
3. If the injector is functioning, clean or replace it if clogged or malfunctioning.

5. Perform Compression Test (if necessary)

1. Remove the spark plug from cylinder 1 (if not already done).
2. Insert the compression tester into the spark plug hole and crank the engine.
3. Compare the reading to manufacturer specifications (typically around 180-200 psi).
   • If compression is low, further investigation into the engine internals may be necessary.