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Why does my 2020 Highlander emit a strong exhaust smell? - Toyota Highlander
Home/Cars/Toyota/Highlander/Fourth Generation (2020-present)/Why does my 2020 Highlander emit a strong exhaust smell?

Why does my 2020 Highlander emit a strong exhaust smell?

Toyota Highlander Fourth Generation (2020-present)

Error Codes
medium
Difficulty
medium
Severity
Navigation
ProblemSymptomsDiagnosisSolution
ProblemSymptomsDiagnosisSolution
3 min read
579 words

Problem Statement

Learn how to diagnose and repair a strong exhaust smell in your 2020 Toyota Highlander. Follow our detailed steps and use the right tools for effective solutions.

Affected Component
exhaust system

Symptoms

  • •Noticeable exhaust odor inside or outside the vehicle
  • •Possible check engine light (CEL) illuminated
  • •Decreased fuel efficiency
  • •Engine running rough or misfiring
  • •Visible smoke or abnormal exhaust color

Diagnostic Steps

  1. 1
  2. 2
  3. 3
  4. 4
  5. 5
  6. 6

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 and wrenches
  • •Screwdrivers
  • •Torque wrench
  • •Inspection mirror
  • •Flashlight
  • •Safety goggles and gloves
  • •Exhaust leak detection fluid (optional)

Additional Information

Affected Component
exhaust system
Difficulty
medium
Severity
medium
Tools Required
8 items

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Back to Generation
Problem: Strong Exhaust Smell in 2020 Toyota Highlander
Tools Required
  • OBD-II scanner
  • Socket set and wrenches
  • Screwdrivers
  • Torque wrench
  • Inspection mirror
  • Flashlight
  • Safety goggles and gloves
  • Exhaust leak detection fluid (optional)
Repair Instructions

Step 1: Fix Exhaust Leaks

  1. Locate the Leak:

    • Start the engine and listen for hissing or popping sounds near the exhaust system.
    • Apply exhaust leak detection fluid at suspected areas to see if bubbles form.
  2. Repair or Replace Components:

    • If a leak is found, tighten the bolts or replace gaskets as necessary.
    • For damaged pipes or mufflers, cut out the damaged section and replace it with a new pipe or component.

Step 2: Address Diagnostic Trouble Codes

  1. Clear Codes:

    • Use the OBD-II scanner to clear any codes and take the vehicle for a test drive to see if the codes reappear.
  2. Replace Faulty Sensors:

    • If an oxygen sensor or other relevant sensor is indicated by the codes, replace it according to manufacturer specifications.

Step 3: Fuel System Repair

  1. Repair Fuel Leaks:
    • If any leaks are detected in the fuel system, replace damaged hoses or components.
    • Ensure all fuel connections are secure.

Step 4: Catalytic Converter Inspection

  1. Examine for Damage:

    • Inspect the catalytic converter for physical damage, discoloration, or any rattling noise indicating internal failure.
  2. Replace if Necessary:

    • If the catalytic converter is damaged, replace it with a new unit per Toyota specifications.

Step 5: Check EGR System

  1. Inspect EGR Valve:

    • Remove and clean the EGR valve if it is clogged. Replace if it shows signs of failure.
  2. Check EGR Passages:

    • Ensure there are no blockages in the EGR passages leading to the intake manifold.
Conclusion

After performing these diagnostics and repairs, monitor the vehicle for any further exhaust smell. If the issue persists, it may be necessary to consult a professional technician for further diagnosis. Regular maintenance checks can help prevent similar issues in the future.