why is my Toyota Corolla E170 (2013-2019) failing emissions test

Toyota Corolla E170 (2013-2019)

Error Codes

2-4 hours

Time

medium

Difficulty

high

Severity

3 min read

556 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 emissions test failure in Toyota Corolla E170. Step-by-step guide with diagnostic procedures and repair instructions.

Affected Component

Exhaust System

Estimated Time

2-4 hours

⚠️ Safety Warnings

Important safety information - read before proceeding

•Disconnect the battery before working on electrical systems.
•Allow the engine to cool before opening the exhaust system.

Symptoms

•Check engine light illuminated
•Increased exhaust smoke
•Unusual smells from the exhaust
•Rough engine idle
•Poor fuel economy
•Failed emissions test report

Diagnostic Steps

1
Scan for error codes using an OBD-II scanner to identify potential issues.
2
Inspect the exhaust system for any visible leaks or damage.
3
Check the condition of the catalytic converter using a temperature probe to measure inlet and outlet temperatures.
4
Examine the oxygen sensors for proper operation and check their voltage output.
5
Verify that the engine is operating at optimal temperature by checking the thermostat and coolant levels.
6
Inspect the air intake system for blockages or leaks that may affect fuel-air mixture.

Solution

💡 Expert Tip

For complex repairs like this, consider taking photos at each step. This helps if you need to reverse a step or consult with a mechanic. Also, keep all removed parts organized - you may need to reference them during reassembly.

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
•Screwdrivers

Parts Required

•Oxygen sensors (upstream and downstream)
•Catalytic converter (if necessary)
•Air filter

Related Faults

Share this solution

Comments

No comments yet

Be the first to share your thoughts

Back to Generation

Diagnostic Steps

1
Scan for error codes using an OBD-II scanner to identify potential issues.
2
Inspect the exhaust system for any visible leaks or damage.
3
Check the condition of the catalytic converter using a temperature probe to measure inlet and outlet temperatures.
4
Examine the oxygen sensors for proper operation and check their voltage output.
5
Verify that the engine is operating at optimal temperature by checking the thermostat and coolant levels.
6
Inspect the air intake system for blockages or leaks that may affect fuel-air mixture.

Solution

1. Preparation

Gather tools and parts needed for the repair.
Ensure the vehicle is parked on a level surface and the engine is cool.
Disconnect the battery to ensure safety while working on electrical components.

2. Replace Faulty Oxygen Sensors

Sub-steps:
- Locate the upstream and downstream oxygen sensors in the exhaust system.
- Use a socket wrench to remove the faulty oxygen sensors.
- Install new oxygen sensors, ensuring they are tightened to the manufacturer's specifications (typically around 30 lb-ft).
- Reconnect the electrical connectors.

3. Replace Catalytic Converter (if necessary)

Sub-steps:
- Remove the exhaust system components connected to the catalytic converter, including bolts and clamps.
- Carefully detach the old catalytic converter.
- Install the new catalytic converter, ensuring proper alignment with the exhaust system.
- Tighten bolts to the manufacturer's specifications (usually around 25 lb-ft).
- Reattach any removed components.

4. Check and Replace Air Filter

Sub-steps:
- Open the air intake housing and remove the old air filter.
- Inspect the air filter housing for debris and clean if necessary.
- Install a new air filter, ensuring it fits snugly in the housing.

5. Reset the Engine Control Unit (ECU)

Sub-steps:
- Reconnect the battery after completing repairs.
- Use the OBD-II scanner to clear any existing trouble codes from the ECU.
- Drive the vehicle for a short distance to allow the ECU to recalibrate.