what does it mean when my Toyota Corolla E210 (2019-2024) has a P0301 code

Solution

1. Preparation

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

2. Replace Spark Plug

• Tools Required: Socket set, torque wrench, spark plug socket.
• Remove the ignition coil from cylinder 1 by unscrewing the mounting bolts.
• Carefully pull out the spark plug using the spark plug socket.
• Inspect the old spark plug for signs of damage or excessive wear.
• Install the new spark plug, ensuring it is torqued to the manufacturer’s specifications (typically around 13-15 lb-ft).
• Reinstall the ignition coil.

3. Check and Replace Ignition Coil (if necessary)

• Tools Required: Multimeter, socket set.
• If the spark plug replacement did not resolve the issue, test the ignition coil with a multimeter to check for proper resistance.
• If defective, remove the faulty ignition coil and install a new one.
• Reconnect all electrical connections securely.

4. Inspect Fuel Injector

• Tools Required: Fuel injector cleaner, fuel pressure gauge.
• Disconnect the fuel line from the fuel injector and use a fuel pressure gauge to check the fuel pressure.
• If pressure is low, check the fuel pump and fuel filter for issues.
• If the fuel injector is suspected to be clogged, use a fuel injector cleaner or replace it with a new one.

5. Perform Compression Test

• Tools Required: Compression tester.
• Remove the spark plug from cylinder 1 and screw in the compression tester.
• Crank the engine and note the compression reading.
• Compare the reading with manufacturer specifications (typically around 180-210 psi).
• If the compression is low, further diagnosis may be needed for internal engine issues.