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What should I do if my 2021 Highlander’s engine is making a knocking sound? - Toyota Highlander
Home/Cars/Toyota/Highlander/Fourth Generation (2020-present)/What should I do if my 2021 Highlander’s engine is making a knocking sound?

What should I do if my 2021 Highlander’s engine is making a knocking sound?

Toyota Highlander Fourth Generation (2020-present)

Error Codes
2-4 hours
Time
medium
Difficulty
high
Severity
Navigation
ProblemSymptomsDiagnosisSolution
ProblemSymptomsDiagnosisSolution
4 min read
646 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 repair a knocking sound in your 2021 Toyota Highlander engine with our step-by-step guide.

Affected Component
engine
Estimated Time
2-4 hours

Symptoms

  • •Knocking Noise
  • •Performance Issues
  • •Warning Lights
  • •Vibration

Diagnostic Steps

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

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
  • •Mechanic’s Stethoscope
  • •Oil Pressure Gauge
  • •Socket Set and Wrenches
  • •Torque Wrench
  • •Screwdrivers
  • •Pliers
  • •Engine Oil
  • •Oil Filter

Additional Information

Affected Component
engine
Estimated Time
2-4 hours
Difficulty
medium
Severity
high
Tools Required
9 items

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Back to Generation

Certainly! If your 2021 Toyota Highlander is making a knocking sound from the engine, it is crucial to address the issue promptly to prevent potential damage. Below are the symptoms, diagnostic steps, required tools, and repair instructions.

Tools Required
  • OBD-II Scanner
  • Mechanic’s Stethoscope
  • Oil Pressure Gauge
  • Socket Set and Wrenches
  • Torque Wrench
  • Screwdrivers
  • Pliers
  • Engine Oil (if needed)
  • Oil Filter (if oil change is necessary)
Repair Instructions

Step 1: Address Low Oil Level

  • Add Engine Oil: If the oil level is low, add the appropriate type and grade of engine oil as specified in the owner's manual. Check for leaks afterward.

Step 2: Oil Change (if necessary)

  • Drain Old Oil:

    1. Raise the vehicle using jack stands.
    2. Place an oil drain pan under the oil pan and remove the oil drain plug using the appropriate socket.
    3. Allow the oil to completely drain.

  • Replace Oil Filter:

    1. Remove the old oil filter using an oil filter wrench.
    2. Apply a bit of new oil to the rubber gasket of the new filter.
    3. Install the new oil filter, tightening it by hand.

  • Refill Engine Oil:

    1. Reinstall the drain plug and torque it to specifications.
    2. Refill the engine with fresh oil using a funnel, checking the level with the dipstick.

Step 3: Inspect for Mechanical Issues

  • Inspect Timing Chain/Belt: If the knocking persists, inspect the timing chain or belt for wear or misalignment.
  • Check Rod Bearings: You may need to remove the oil pan to inspect rod bearings for wear. This requires:
    1. Removing the oil pan bolts and gently prying the oil pan loose.
    2. Inspecting bearings and replacing them if they are worn.

Step 4: Inspect Valvetrain Components

  • Valve Adjustment: If applicable, check the valve clearance and adjust as necessary.
  • Inspect Lifters: Noisy lifters can cause knocking sounds. Replace any faulty lifters.

Step 5: Reassemble and Test

  • Reassemble the Engine: Ensure all components are assembled correctly.
  • Start the Engine: Monitor for the knocking sound and check for leaks.
  • Test Drive: Take the vehicle for a short test drive to ensure the issue is resolved.
Conclusion

If the knocking sound continues after completing these steps, it may be indicative of more severe internal engine damage (e.g., piston slap, bearing failure) and require professional diagnosis and repair. Always consider reaching out to a qualified technician if you are unsure at any step or if the issue persists.