Inspection Procedure 11: Abnormal sound occurs during idling.




PROBABLE CAUSES



  • Malfunction of the engine: Abnormal sound of auxiliary parts
  • A/T fluid level
  • Installation of torque converter
  • A/T failure: Hydraulic system (valve body assembly, hydraulic circuit)
note Inspection items for abnormal sound
  1. Check of sound source and incoming route (radiated sound, propagation sound, resonance, etc.), and measurement at driver’s seat, front passenger’s seat, and rear passenger’s seat
  2. Change of sound during cold and after warm up (Change of fluid, and hydraulic pressure)
  3. Change of sound with the engine speed
  4. Check of tone, and continuous/discontinuous sound

DIAGNOSIS PROCEDURE


STEP 1. Check the engine performance.


Check the sound of engine, auxiliary parts, and resonance/nonresonance.

Q. Is the check result normal?

Go to Step 2.
Repair the failure, and perform adjustment.

STEP 2. Check the A/T fluid level.


Check if the A/T fluid level is adequate.

Q. Is the check result normal?

Go to Step 4.
Go to Step 3.

STEP 3. Check and repair the leakage point of the A/T fluid.


Check and repair the leakage point of the A/T fluid, and adjust the A/T fluid level. Then check if the abnormal sound is generated.

Q. Is the check result normal?

The procedure is complete.
Go to Step 4.

STEP 4. Check the A/T fluid.


Check the A/T fluid for burning, fouling, and foreign material.

Q. Is the check result normal?

Go to Step 5.
Go to Step 8.

STEP 5. Retest the system.


Check if the abnormal sound during idling occurs with vibration.

Q. Is the check result normal?

Go to Step 6.
Go to Step 7.

STEP 6. Check the torque converter.


Check the torque converter installation, change the installation phase, and then check the trouble symptom.

Q. Is the check result normal?

The procedure is complete.
Go to Step 7.

STEP 7. Compare with another same model vehicle.


Q. Is there a difference from the same model vehicle?

Go to Step 8.
The procedure is complete.

STEP 8. Remove the transmission assembly from the vehicle.


Disassemble and check the transmission assembly to check if there is a foreign material inside.

Q. Is the check result satisfactory?

Replace the transmission assembly.
Replace the failure part.