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

Solution

1. Preparation

• Gather tools and parts needed for the repair.
• Disconnect the negative battery terminal to prevent electrical shorts.
• Allow the engine to cool before proceeding.

2. Replace Spark Plug and Ignition Coil

1. Remove Engine Cover (if applicable)

   • Use a socket set to remove any bolts securing the cover.
   • Carefully lift the cover off and set it aside.

2. Access Cylinder 1 Components

   • Locate cylinder 1 ignition coil and spark plug (usually the first spark plug on the left side when facing the engine).

3. Remove Ignition Coil

   • Disconnect the electrical connector from the ignition coil.
   • Remove the bolts securing the ignition coil using a socket set.
   • Gently pull the ignition coil out of the cylinder head.

4. Replace Spark Plug

   • Use a spark plug socket to remove the old spark plug from cylinder 1.
   • Check the gap on the new spark plug and adjust it to manufacturer specifications (typically around 0.044 inches for most Toyota models).
   • Install the new spark plug and tighten it to the manufacturer's torque specification (usually around 13 lb-ft).

5. Reinstall Ignition Coil

   • Place the new or inspected ignition coil onto the spark plug.
   • Secure it with the bolts and reconnect the electrical connector.

3. Check Fuel Injector

1. Inspect Fuel Injector

   • If the ignition coil and spark plug are fine, check the fuel injector for cylinder 1.
   • Disconnect the fuel injector connector.
   • Use a multimeter to test the injector resistance; it should be within manufacturer specifications (typically around 12-16 ohms).

2. Replace Fuel Injector (if necessary)

   • If the injector is faulty, remove it by unscrewing any retaining clips and pulling it out of the fuel rail.
   • Install the new fuel injector and reattach the connector.