FAULTBASE
Error CodesASKCars
© 2025 FAULTBASE
All rights reserved.
v2.0.0 • Production
ContactPrivacyImpressum
Home/Cars/Toyota/Corolla/E210 (2019-2024)/my Toyota Corolla E210 (2019-2024) has a P0303 code, what does this mean?

my Toyota Corolla E210 (2019-2024) has a P0303 code, what does this mean?

Toyota Corolla E210 (2019-2024)

Error Codes
Severity: highDifficulty: mediumError Code: P03032-4 hours
3 min read
566 words

⚠️ Safety Warning

This issue requires immediate attention. If you are not experienced with automotive repairs, consult a professional mechanic. Working on critical systems can be dangerous.

Problem Statement

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

Error Code
P0303
Affected Component
Engine
Estimated Time
2-4 hours

Safety Warnings

  • ⚠Disconnect the battery before working on electrical systems.
  • ⚠Allow engine to cool before opening any components.

Symptoms

  • •Check engine light illuminated
  • •Rough idle while the engine is running
  • •Decreased engine power during acceleration
  • •Increased fuel consumption
  • •Engine stalling in some cases

Diagnostic Steps

  1. 1Scan the vehicle’s onboard diagnostic system using an OBD-II scanner to confirm the P0303 code and check for any additional codes.
  2. 2Inspect the ignition system components, including spark plugs and ignition coils, specifically for cylinder three.
  3. 3Check the fuel injector operation for cylinder three, ensuring it is functioning properly.
  4. 4Perform a visual inspection of the wiring and connections related to the ignition coil and fuel injector for signs of damage or corrosion.
  5. 5Conduct a compression test on cylinder three to check for mechanical issues such as a blown head gasket or valve problems.
  6. 6Test the fuel pressure to ensure the fuel system is supplying adequate pressure to the engine.

Solution

Solution

1. Preparation

  • Gather all necessary tools and parts.
  • Disconnect the battery to prevent electrical shock or short circuits.
  • Ensure the engine is cool before starting the work.

2. Inspect and Replace Spark Plug

  • Remove the engine cover if applicable.
  • Use a socket set to remove the spark plug from cylinder three.
  • Inspect the spark plug for wear or damage. If it is worn or fouled, replace it with a new OEM spark plug.
  • Torque the new spark plug to the manufacturer’s specifications (typically around 13-15 lb-ft).

3. Inspect and Replace Ignition Coil

  • Disconnect the wiring harness from the ignition coil for cylinder three.
  • Remove the ignition coil using a socket set.
  • Inspect the ignition coil for signs of wear or damage. Replace it if necessary with a new OEM coil.
  • Reinstall the ignition coil and reconnect the wiring harness securely.

4. Inspect Fuel Injector

  • Disconnect the fuel injector connector and remove the fuel rail if necessary to access the injector.
  • Inspect the fuel injector for clogs or damage. If it appears faulty, replace it with a new OEM injector.
  • Reassemble the fuel rail and connect the injector properly.

5. Reconnect Battery and Clear Codes

  • Reconnect the battery terminals.
  • Use the OBD-II scanner to clear the P0303 code from the vehicle’s computer.

Verification

After completing the repair, verify that the issue has been resolved:

  • ✓Test the affected component to ensure it functions correctly
  • ✓Check for any error codes or warning lights
  • ✓Monitor the vehicle for a few days to ensure the issue does not recur

Prevention Tips

To prevent this issue from occurring again:

  • •Follow the manufacturer's recommended maintenance schedule
  • •Address warning signs early before they develop into major issues
  • •Use quality parts and fluids recommended for your vehicle
  • •Keep detailed records of all repairs and maintenance

Tools & Equipment Required

  • •OBD-II scanner
  • •Socket set
  • •Torque wrench
  • •Compression tester
  • •Fuel pressure gauge

Parts Required

  • •OEM spark plug
  • •OEM ignition coil (if necessary)
  • •OEM fuel injector (if necessary)

Additional Information

Error Code
P0303
Affected Component
Engine
Estimated Time
2-4 hours
Difficulty
medium
Severity
high
Tools Required
5 items
Parts Required
3 items

Related Faults

  1. How can I fix a leaking sunroof in my 2023 Toyota Corolla E210?

    To fix a leaking sunroof in your 2023 Toyota Corolla E210, follow these detailed steps. A leaking sunroof can cause water to enter the cabin, leading to potential interior damage and mold growth. Comm

  2. How do I fix a malfunctioning rearview camera in my 2019 Toyota Corolla E210?

    Diagnose and fix rearview camera issues in your 2019 Toyota Corolla E210 with this step-by-step guide. Ensure safety with a functional camera.

    Electrical4 symptoms

  3. What could cause uneven tire wear on my 2022 Toyota Corolla E210?

    Diagnose and fix uneven tire wear on your 2022 Toyota Corolla E210 with this step-by-step guide. Ensure optimal tire performance.

    Tires5 symptoms

  4. How do I address a persistent brake squeal in my 2019 Toyota Corolla E210?

    Address persistent brake squeal in your 2019 Toyota Corolla E210 with this detailed guide. Learn diagnostic and repair steps.

    Brakes3 symptoms

  5. What could cause the power windows to malfunction in my 2022 Toyota Corolla?

    When experiencing power window malfunctions in a 2022 Toyota Corolla E210, several potential causes could be responsible. Below are detailed steps to diagnose and resolve the issue:

  6. Why might the Toyota Corolla E210's rearview camera display a blank screen?

    When a Toyota Corolla E210 (2019-2024) experiences a blank screen on the rearview camera display, it can be due to several potential issues. Here is a detailed guide to diagnose and potentially resolv

Share this solution

Comments

Sign in to share your thoughts

Sign In

No comments yet

Be the first to share your thoughts

Back to Generation