how to fix P0301 code for my Toyota Corolla E140 (2006-2013)

Solution

1. Preparation

• Gather necessary tools and parts.
• Disconnect the battery to prevent electrical shorts.
• Allow the engine to cool down before starting repairs.

2. Inspect and Replace Spark Plug

• Tools Required: Spark plug socket, ratchet, torque wrench
• Remove the spark plug wire from cylinder 1.
• Use the spark plug socket to carefully remove the spark plug.
• Inspect the spark plug for signs of wear or fouling. Replace if needed.
• Install a new spark plug, torquing it to the manufacturer's specification (usually around 13-16 lb-ft).

3. Check and Replace Ignition Coil

• Tools Required: Ratchet, socket set
• Remove the ignition coil from cylinder 1 by unscrewing the mounting bolts.
• Visually inspect the ignition coil for cracks or damage. Test it using a multimeter if necessary.
• If faulty, replace the ignition coil with a new one and reconnect all wiring.

4. Perform Compression Test

• Tools Required: Compression gauge
• Remove the spark plug from cylinder 1.
• Insert the compression gauge into the spark plug hole.
• Crank the engine several times to get a reading. The compression should be within the manufacturer's specified range (typically 180-210 psi).
• If low compression is detected, further investigation on cylinder health (e.g., head gasket, piston rings) is needed.

5. Inspect and Clean Fuel Injector

• Tools Required: Fuel injector cleaner, basic hand tools
• Remove the fuel rail to access the injector for cylinder 1.
• Inspect the injector for clogs or leaks. Clean with a fuel injector cleaner if necessary.
• Reinstall the injector and fuel rail, ensuring all seals are secure.