how to fix P0301 code in Toyota Corolla E170 (2013-2019)

Solution

1. Preparation

• Gather tools and parts.
• Disconnect the negative battery terminal.
• Allow the engine to cool.

2. Inspect and Replace Spark Plug

• Tools Required: Socket set, gap gauge, torque wrench
• Remove the ignition coil by unscrewing the bolts and disconnecting the electrical connector.
• Unscrew the spark plug using the socket set. Inspect for fouling or damage.
• If the spark plug is worn out, replace it with a new one, ensuring the gap is set according to manufacturer specifications (typically 0.043 inches for a 2013 Toyota Corolla).
• Reinstall the spark plug and torque it to the manufacturer’s specification (approximately 13 lb-ft).

3. Inspect and Replace Ignition Coil

• Tools Required: Socket set, torque wrench
• Remove the ignition coil from cylinder 1.
• Inspect for any physical damage. If damaged, replace with a new ignition coil.
• Reinstall the ignition coil and torque it to the specified value (approximately 7 lb-ft).

4. Inspect and Replace Fuel Injector

• Tools Required: Fuel line removal tool, socket set
• Disconnect the fuel injector connector.
• Remove the fuel rail if necessary to access the injector.
• Inspect the injector for clogs or damages. If faulty, replace the injector with a new one.
• Reassemble and connect the fuel rail and injector connector.

5. Compression Test

• Tools Required: Compression tester
• Remove all spark plugs to perform a compression test.
• Insert the compression tester into cylinder 1 and crank the engine.
• Check the compression reading against manufacturer specifications (typically between 180-200 psi).
• If compression is low, further investigation for internal engine damage may be necessary.

6. Reconnect Battery and Clear Codes

• Reconnect the negative battery terminal.
• Use the OBD-II scanner to clear the P0301 code and any other stored codes.