Inspection Procedure 11: The Feeling of Impact or Vibration when Accelerating


COMMENTS ON TROUBLE SYMPTOM



  • The failure could possibly be caused by the ignition leak occurring in association with the increase in the voltage required by the spark plug during the acceleration, failed electronic-controlled throttle valve system and so on.

PROBABLE CAUSES



  • Failed ignition system
  • Failed electronic-controlled throttle valve system
  • Contamination around the throttle valve
  • Failed TC-SST
  • Failed engine-ECU

DIAGNOSIS PROCEDURE
note To protect the TC-SST, the TC-SST-ECU outputs, into the engine-ECU, the request signal to reduce the engine torque according to the operation condition, Based on the signal, the engine-ECU closes the throttle valve, retards the ignition or carries out fuel cut. At that time, the engine output seems to temporarily reduce, but there is no malfunction.

STEP 1. M.U.T.-III diagnosis code

Q. Is diagnosis code set?
Inspection chart for diagnosis code (Refer to ).
Go to Step 2.

STEP 2. M.U.T.-III diagnosis code
note When the TC-SST has a malfunction, the TC-SST-ECU might output the request signal of reducing the engine torque in order to protect the TC-SST.

  • Confirm the diagnosis code is set from TC-SST-ECU.

Q. Is the diagnosis code set?
Perform troubleshooting of TC-SST system (Refer to GROUP 22E - Diagnosis Troubleshooting <TC-SST> - Diagnosis Code Chart ).
Go to Step 3.

STEP 3. M.U.T.-III data list

  • Refer to Data List Reference Table .

  1. Item 11: Accelerator pedal position sensor (main)
  2. Item 12: Accelerator pedal position sensor (sub)
  3. Item 13: Throttle position sensor (main)
  4. Item 15: Throttle position sensor (sub)

Q. Are the check results normal?
Go to Step 4.
Perform the diagnosis code classified check procedure for the sensor that has shown an abnormal data value (Refer to Inspection Chart for Diagnosis Code ).

STEP 4. Check throttle body (throttle valve portion) contamination.

Q. Is the check result normal?
Go to Step 5.
Clean throttle body (throttle valve portion) (Refer to ).

STEP 5. Visual check of ignition spark.

  • Remove the spark plug and install it to the ignition coil.
  • Connect the ignition coil connector.
  • Disconnect all injector connectors.
  • At the engine start, check each spark plug produces a spark.

Q. Is the check result normal?
Replace the engine-ECU.
Check ignition circuit system (Refer to Inspection Procedure 22 ).