how to fix P0303 misfire code in my Toyota Corolla E210 (2019-2024)

Learn how to diagnose and fix P0303 cylinder 3 misfire in Toyota Corolla E210. Step-by-step guide with diagnostic procedures and repair instructions.

Solution

1. Preparation

• Gather necessary tools and parts.
• Disconnect the negative battery terminal to prevent electrical shorts.

2. Inspect and Replace Spark Plug

• Remove the ignition coil cover if applicable.
• Use a socket set to remove the spark plug for cylinder 3.
  • Tools Required: Socket set, torque wrench, spark plug socket.
• Inspect the spark plug for wear (color, electrode condition).
• Replace with a new spark plug if damaged or worn.
  • Torque Specification: 13 lb-ft (17 Nm) for spark plugs.

3. Test and Replace Ignition Coil

• Remove the ignition coil for cylinder 3.
• Test the ignition coil with a multimeter for resistance.
  • Specification: Typically 0.5 to 2.0 ohms for primary resistance.
• Replace the ignition coil if it fails the test.
  • Tools Required: Multimeter, socket set.

4. Inspect and Clean or Replace Fuel Injector

• Disconnect the fuel injector connector.
• Remove the fuel injector from cylinder 3 using the appropriate tools.
  • Tools Required: Fuel injector puller, socket set.
• Inspect the injector for clogs or wear.
• Clean the injector using a fuel injector cleaner or replace with a new injector if necessary.

5. Perform Compression Test

• Remove the spark plug and ignition coil from cylinder 3.
• Insert a compression gauge into the spark plug hole.
• Crank the engine and read the compression value.
  • Specification: Typically around 180 psi (check manufacturer specifications).
• If low compression is detected, further investigation into the cylinder head or piston rings may be needed.